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Post by tornado on Mar 15, 2016 12:24:21 GMT -5
866. Morgantown, West Virginia, 18 (19) Jun 2015:
Between 0000Z and 0300Z on the 19th UTC (18 Jun EDT); Morgantown (KMGW) recorded some light rain, and a peak wind gust to 27 knots:
METAR KMGW 182353Z VRB04KT 10SM CLR 28/19 A2998 RMK AO2 SLP141 T02830189 10306 20283 55005
METAR KMGW 190053Z 00000KT 10SM BKN047 BKN065 27/19 A2999 RMK AO2 SLP143 T02670189
METAR KMGW 190153Z 00000KT 10SM FEW028 SCT034 BKN045 24/19 A3000 RMK AO2 SLP148 T02440189
METAR KMGW 190253Z VRB03KT 8SM -RA FEW019 BKN110 22/18 A3006 RMK AO2 PK WND 24027/0214 RAB12 SLP168 P0005 60005 T02220183 53026
If a nearby thunderstorm was present, that would explain the rain and the wind. There was most certainly lightning within 10 miles of Morgantown:
Within the red 5-mile range ring around KMGW, there were 16 lightning strikes which met TS criteria. No TS was reported by KMGW. Between the red and green range rings, there were 170 lightning strikes which met VCTS criteria. No VCTS was reported by KMGW. Is it because the nearest lightning bolts struck 2.5 miles E and SSW of KMGW, that 186 lightning strikes went unreported?
At 0053Z, a CB, TS, or LTG could have gotten mentioned due to a level 6 cell about 8 miles NW of KMGW (radar valid 0050Z):
But no hazard was mentioned in the 0053Z METAR, relating to that storm. By 0150Z, there were still level 5 cells in the area; one of which produced most of the lightning, to the east:
Hopefully, pilots in the area of Morgantown, were aware of the hazards. But TS or VCTS didn’t get reported that evening, even though there had been 186 lightning strikes within 10 miles!
867. Paducah, Kentucky, 18 (19) Jun 2015:
Late on the 18th, that it was the 19th UTC; Paducah (KPAH) recorded a VCTS:
METAR KPAH 190253Z 14004KT 10SM SCT080 26/21 A2998 RMK AO2 LTG DSNT W SLP147 T02560211 53012
SPECI KPAH 190346Z 27010G15KT 10SM VCTS FEW020 BKN075 OVC090 26/20 A2999 RMK AO2 T02560200
METAR KPAH 190353Z 17010G17KT 10SM VCTS FEW021 BKN080 OVC095 27/22 A2998 RMK AO2 SLP148 T02670217
SPECI KPAH 190440Z AUTO 00000KT 10SM BKN100 OVC120 24/20 A2998 RMK AO2 LTG DSNT N-E RAB02E35 P0000 T02390200
METAR KPAH 190453Z AUTO 36003KT 10SM FEW055 OVC100 23/19 A2998 RMK AO2 LTG DSNT N AND NE RAB02E35 SLP146 P0000 T02330194
That would mean there was no lightning within 5 miles. But, there was:
3 lightning bolts struck within the red 5-mile range ring around KPAH, to the north. The closest hit about 3 miles away:
ALDARS did not measure the distance to the 3 nearest lightning strikes correctly.
868. New Bern, North Carolina, 18-19 Jun 2015:
New Bern (KEWN) had a lightning issue for several hours, entailing at least 2 thunderstorms. That is because the site had its ASOS placed in AUTO/TSNO mode since 9:54 a.m.:
METAR KEWN 181354Z AUTO 21007KT 10SM 28/ A3008 RMK AO2 SLP185 T0283 TSNO
METAR KEWN 181454Z AUTO 19003KT 10SM CLR 31/ A3008 RMK AO2 SLP185 6//// T0306 TSNO $
METAR KEWN 181554Z AUTO VRB06KT 10SM CLR 32/ A3008 RMK AO2 SLP184 T0322 TSNO
METAR KEWN 181654Z AUTO 18005KT 10SM CLR 32/ A3007 RMK AO2 SLP181 T0322 TSNO
METAR KEWN 181754Z AUTO 27007KT 10SM CLR 33/ A3005 RMK AO2 SLP175 6//// T0328 10333 20250 58010 TSNO
METAR KEWN 181854Z AUTO 10SM CLR 34/ A3003 RMK AO2 SLP169 T0339 TSNO
METAR KEWN 181954Z AUTO 00000KT 10SM FEW038 34/ A3000 RMK AO2 SLP159 T0339 TSNO
METAR KEWN 182054Z AUTO VRB03KT 10SM SCT043 34/ A2999 RMK AO2 SLP156 T0344 56019 TSNO
METAR KEWN 182154Z AUTO 18011KT 10SM FEW041 SCT055 33/ A2998 RMK AO2 SLP153 T0333 TSNO
METAR KEWN 182254Z AUTO 00000KT 10SM FEW036 FEW060 SCT080 26/ A3002 RMK AO2 RAB27E52 SLP163 P0002 T0256 TSNO
METAR KEWN 182354Z AUTO 21005KT 10SM CLR 25/ A3001 RMK AO2 RAB2257E11 SLP162 P0000 60002 T0250 10350 20250 53006 TSNO
METAR KEWN 190054Z AUTO 20004KT 10SM CLR 25/ A3000 RMK AO2 SLP158 T0250 TSNO
METAR KEWN 190154Z AUTO 28005KT 10SM CLR 25/ A3002 RMK AO2 SLP164 T0250 TSNO
METAR KEWN 190254Z AUTO 28005KT 10SM CLR 25/ A3007 RMK AO2 SLP180 T0250 53018 TSNO $
METAR KEWN 190354Z AUTO 30008KT 10SM FEW075 25/ A3008 RMK AO2 SLP187 T0250 TSNO $
METAR KEWN 190454Z AUTO 30005KT 10SM -RA FEW044 SCT095 SCT120 24/ A3009 RMK AO2 RAB10 SLP187 P0021 T0239 403500239 TSNO $ METAR KEWN 190533Z AUTO 24007KT 1 3/4SM +RA SCT033 BKN070 BKN110 23/ A3009 RMK AO2 P0018 T0233 TSNO $
SPECI KEWN 190542Z AUTO 00000KT 3SM RA SCT035 SCT075 BKN090 23/ A3008 RMK AO2 PRESFR P0020 T0233 TSNO $
METAR KEWN 190554Z AUTO 32003KT 10SM -RA FEW035 BKN080 OVC100 23/ A3006 RMK AO2 PRESFR SLP179 P0020 60041 T0233 10256 20233 58001 TSNO $
The 18th was a Thursday, and the 19th was a Friday. ASOS should not have been in AUTO mode while the control tower was open on Thursday, let alone be in TSNO mode. Yet it was, thereby missing all the lightning plotted below:
There were 2 separate thunderstorms that struck the area. One has its lightning strikes plotted in purple; the other has its strikes plotted in orange/yellow. Zooming in, the first thunderstorm hit between 2200-2300Z:
That storm produced 5 lightning strikes within 5 miles, meeting TS criteria. A total of 32 lightning bolts struck within 10 miles. That was 6-7 p.m. EDT, and the control tower was open. The second thunderstorm hit overnight, while the tower was closed. It produced more and closer lightning, lasted longer; and produced the heavy rain at 0533Z:
Yet, ALDARS wasn’t given a chance to detect that lightning and report a thunderstorm, as it was switched off. Why was that? Was it because ASOS was not reporting a dew point, so LAWRS signed off ASOS; placing it in not only AUTO, but TSNO mode? Based on the following sequence of observations, that is what happened:
SPECI KEWN 180809Z AUTO 00000KT 10SM VCTS -RA SCT019 BKN065 OVC090 25/23 A3010 RMK AO2 LTG DSNT NE AND SW RAB01 P0000 T02500228
METAR KEWN 180854Z AUTO 12003KT 10SM -RA FEW070 SCT085 BKN110 24/23 A3007 RMK AO2 LTG DSNT E AND S RAB01E22B37 SLP183 P0001 60001 T02440228 58004
METAR KEWN 180854Z AUTO 12003KT 10SM -RA FEW070 SCT085 BKN110 24/23 A3007 RMK AO2 LTG DSNT E AND S RAB01E22B37 SLP183 P0001 60001 T02440228 58004
METAR KEWN 180954Z AUTO 36009KT 10SM SCT013 SCT060 25/23 A3009 RMK AO2 LTG DSNT W RAE10 SLP189 P0000 T02500233
SPECI KEWN 181002Z AUTO 36006KT 10SM FEW009 SCT013 BKN060 24/23 A3010 RMK AO2 LTG DSNT W T02440228
METAR KEWN 181154Z AUTO 18003KT 10SM FEW100 25/23 A3010 RMK AO2 SLP191 60001 70037 T02500233 10256 20239 $
METAR KEWN 181254Z AUTO 17003KT 10SM CLR 27/23 A3009 RMK AO2 SLP188 T02670233 $
METAR KEWN 181354Z AUTO 21007KT 10SM 28/ A3008 RMK AO2 SLP185 T0283 TSNO
So earlier on the 18th, ALDARS was enabled, and reporting VCTS and LTG DSNT as it was programmed to do. But as soon as the dew point went missing, TSNO appeared in remarks. Someone switched ALDARS off at that point- not switching it back on until 1:54 p.m. on Sat 20 Jun- a period of over 2 days:
METAR KEWN 201754Z 14005KT 10SM SCT033 BKN043 33/26 A3002 RMK AO2 SLP164 T03280256 58009
LAWRS inadvertently switched off ALDARS, resulting in 2 thunderstorms going unreported; one on June 18th, and one on June 19th.
869. Roswell, New Mexico, 19 Jun 2015:
Roswell (KROW) must have ALDARS installed. Otherwise, it would not have reported VCTS on 5 Jun, while LAWRS was signed on to ASOS:
SPECI KROW 052301Z 29012KT 10SM VCTS SCT065 25/14 A3001 RMK AO2 WSHFT 2247 LTG DSNT SW-N PRESRR T02500144
The site also reported VCTS on 6 Jun, after the control closed for the evening:
SPECI KROW 070506Z AUTO 11009KT 10SM VCTS -RA SCT044 BKN065 OVC100 23/13 A3000 RMK AO2 LTG DSNT S AND W RAB0455 P0000 T02280128
So when ALDARS was switched off, and placed in TSNO mode on the evening of 18 Jun, ALDARS had no chance to detect this lightning near Roswell:
Considering that one lightning bolt appears to have hit runway 3/21, near taxiway F; you’d think the FAA or Roswell Airport would want a record of that:
On 2 different nights in June 2015, thunderstorms passed over the Roswell area. One got reported; but the other didn’t, because ALDARS had been disabled.
870. Spring Hill-Brooksville, Florida, 19 Jun 2015:
Brooksville Airport (KBKV) is a level D LAWRS site with ALDARS, just outside Spring Hill; which itself is not far north of Tampa. On 19 Jun, KBKV recorded VCTS, 3 separate times:
METAR KBKV 191453Z 30009KT 10SM SCT026 BKN049 OVC060 28/23 A3013 RMK AO2 LTG DSNT ALQDS SLP201 T02830228 50003
SPECI KBKV 191537Z 00000KT 10SM VCTS -RA SCT034 BKN060 OVC075 28/25 A3014 RMK AO2 LTG DSNT N AND NE AND S RAB10 P0005 T02780250
METAR KBKV 191553Z 24004KT 10SM VCTS -RA SCT040 SCT055 BKN070 29/25 A3013 RMK AO2 LTG DSNT N AND NE AND S RAB10 SLP199 P0005 T02890250
METAR KBKV 191653Z 04009KT 10SM VCTS FEW032 29/24 A3013 RMK AO2 LTG DSNT ALQDS RAE1558 SLP201 P0000 T02940244
SPECI KBKV 191717Z 07005KT 10SM CLR 28/23 A3013 RMK AO2 LTG DSNT NE-S T02830233
SPECI KBKV 191727Z 08007KT 10SM VCTS CLR 28/24 A3013 RMK AO2 LTG DSNT E-SW T02830239
METAR KBKV 191753Z VRB03KT 10SM CLR 31/24 A3012 RMK AO2 LTG DSNT E-SW SLP196 60005 T03110239 10311 20256 58005
METAR KBKV 191806Z 05003KT 10SM VCTS CLR 31/23 A3012 RMK AO2 LTG DSNT E-SW T03060233
METAR KBKV 191829Z 19004KT 10SM CLR 30/24 A3011 RMK AO2 LTG DSNT SE AND S T03000239
METAR KBKV 191853Z 17007KT 10SM CLR 29/24 A3010 RMK AO2 LTG DSNT N SLP190 T02890239
That period was from 11 a.m. to 3 p.m. EDT. On a lightning display map, one would expect to see 3 different colors of lightning plots, corresponding to the 3 different VCTS reports. That is partially the case:
However, while there were the expected 3 different colors of lightning plots (purple, red and orange); not all of the lightning was outside of 5 miles. The first of the 3 VCTS reports, was actually a thunderstorm that produced 5 lightning strikes within 5 miles of KBKV. That makes a bit of sense, as it was the only thunderstorm accompanied by rain at Brooksville Airport. But ALDARS should have reported it as TS, not VCTS. After all, the closest lightning from that storm, struck about 1.5 miles SW of the W end of runway 9/27:
3 times that day, VCTS was reported at KBKV. One of those times, VCTS was not accurate, and TS ought to have been reported. But, how will pilots and ground crews know when ALDARS is accurate, and when it’s not?
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Post by tornado on Mar 15, 2016 13:46:59 GMT -5
871. Ft. Pierce, Florida, 19 Jun 2015:
Between 1800-2000Z at Ft. Pierce (KFPR), ALDARS detected some lightning 10-30 miles from the airport (LTG DSNT NW):
METAR KFPR 191753Z 10010KT 10SM CLR 33/23 A3007 RMK AO2 SLP183 T03330228 10339 20267 58013
METAR KFPR 191853Z 10011KT 10SM CLR 33/23 A3007 RMK AO2 SLP180 LTG DSNT NW T03330233
METAR KFPR 191953Z 11009KT 10SM CLR 33/23 A3006 RMK AO2 SLP178 T03280228
That didn’t match the lightning data; or at least, ALDARS filed incomplete information:
Though there was plenty of LTG DSNT NW, as ALDARS reported; what of the 8 lightning strikes, 5-10 miles from KFPR, that met VCTS criteria? What about the 2 lightning strikes within 5 miles of KFPR, that met TS criteria? Lightning 3 miles away, didn’t get detected by ALDARS:
Since the control tower was open, lightning that slipped past ALDARS, didn’t get reported by LAWRS either. Ft. Pierce had an unrecorded thunderstorm on June 19th.
872. Southwest Florida International Airport, Ft. Myers, Florida, 19 Jun 2015:
Southwest Florida International Airport (KRSW) in Ft. Myers recorded VCTS between 1905-2112Z:
METAR KRSW 191853Z 14004KT 10SM SCT048 BKN055 BKN085 32/22 A3006 RMK AO2 LTG DSNT NW SLP177 T03220222
SPECI KRSW 191905Z 17004KT 10SM VCTS FEW046 BKN065 BKN080 32/22 A3006 RMK AO2 LTG DSNT NW T03220222
METAR KRSW 191953Z 31011KT 10SM VCTS FEW060 SCT075 BKN095 28/22 A3005 RMK AO2 LTG DSNT W-N SLP174 T02780217
METAR KRSW 192053Z 29007KT 10SM VCTS CLR 29/21 A3005 RMK AO2 LTG DSNT W-N SLP172 T02890211 56010
SPECI KRSW 192112Z 32006KT 10SM CLR 29/21 A3003 RMK AO2 LTG DSNT W-NE T02940211
While there was lightning that met VCTS criteria, as ALDARS recorded; there was also closer lightning:
There were 5 lightning strikes, W-NW, that hit within 5 miles of KRSW; those met TS criteria, but no TS was recorded. The nearest of those bolts, struck about 3 miles to the NW:
KRSW reported VCTS, when at least part of that time, TS was justified.
873. N. Myrtle Beach, South Carolina, 19 Jun 2015:
N. Myrtle Beach (KCRE) recorded VCTS from 2053-2205Z:
METAR KCRE 191953Z 20012KT 10SM CLR 31/26 A3000 RMK AO1 LTG DSNT SW SLP160 T03110261
METAR KCRE 192053Z 20013KT 10SM VCTS CLR 30/25 A2999 RMK AO1 LTG DSNT SW-NW SLP157 T03000250 56012
METAR KCRE 192153Z 32005KT 10SM VCTS FEW038 SCT110 29/22 A2997 RMK AO1 LTG DSNT NW-NE SLP149 T02890222
SPECI KCRE 192205Z 00000KT 10SM CLR 29/23 A2996 RMK AO1 LTG DSNT NW-NE T02890228
There were 2 lightning bolts, closer than 5 miles, that ALDARS didn’t report:
 
Were there hazards within 5 miles? The radar at 2050Z (the VCTS was started 3 minutes later) showed a level 5 cell as close as 3 miles to the NW of the airport:
Yet, clear skies were recorded in the official weather report! That report had all the hazards outside 10 miles: VCTS CLR LTG DSNT SW-NW; while ignoring a level 5 cell within 5 miles!
The FAA ditched the claim that “390 LAWRS sites provide accurate weather reporting”; and replaced it with “390 LAWRS sites provide critical weather reporting”. Is that true?
874. Kissimmee, Florida, 19 Jun 2015:
This won’t be a case of an unreported thunderstorm; but, a misreported thunderstorm.
Kissimmee is a D level site, not required to report thunderstorms. But between 19/2000-20/0000Z on 19 Jun 2015, they made an attempt:
METAR KISM 191950Z 27007KT 10SM SCT050 TCU 35/23 A3004
METAR KISM 192050Z 26007KT 10SM VCSH SCT060 TCU 36/22 A3003
METAR KISM 192150Z 04005KT 10SM VCSH BKN60 TCU 32/22 A3003 RMK TS E MOV LIT
METAR KISM 192250Z 01011G18KT 10SM VCSH BKN050 27/24 A3004 RMK TS E MOV LIT
METAR KISM 192350Z 09009G20KT 10SM VCSH FEW011 BKN050 27/24 A3009 RMK TS SE MOV LIT
The LAWRS observers felt it was more important to get “showers in the vicinity” (VCSH) into present weather, than the phenomena causing the showers (which would have been CB, not TCU, once thunder began). “Thunderstorm east, moving little” was relegated to remarks; when thunderstorms, if reported, are required to be listed in present weather. In essence, the lightning strikes on these maps, were misreported:
 
That’s not really helpful, considering the nearest bolt struck about 3,000 feet SW of the end of runway 6/24.
875. Laredo, Texas, 19 Jun 2015:
Laredo (KLRD) recorded VCTS from 2340-0008Z:
METAR KLRD 192156Z 12009KT 10SM CLR 33/20 A2998 RMK AO2 T03270200 SLP138
METAR KLRD 192256Z 09003KT 10SM CLR 32/21 A2997 RMK AO2 T03160205 SLP136
SPECI KLRD 192341Z 11014KT 10SM FEW041 SCT075 30/23 A2997 RMK AO2 TSB40E41
SPECI KLRD 192349Z 12012KT 10SM VCTS FEW041 30/23 A2998 RMK AO2 LTG DSNT S AND SW TSB40E41B43
METAR KLRD 192356Z 12014KT 10SM VCTS CLR 30/23 A2999 RMK AO2 55000 T03000227 10344 20300 TSB40E41B43 SLP144
SPECI KLRD 200008Z 19008KT 10SM SCT032 BKN045 28/22 A3000 RMK AO2 TSE08 WSHFT 2349
METAR KLRD 200056Z 00000KT 10SM -RA FEW029 SCT043 26/23 A3001 RMK AO2 T02610227 TSE08RAB17 P0000 WSHFT 2349 SLP149
It’s uncertain what ALDARS was trying to do, by the 1-minute thunderstorm ending at 2341Z. Perhaps it was making a failed attempt to report lightning within 5 miles:
There certainly was lightning within 5 miles; as the 2 nearest bolts, NE AND SW, struck about a mile from airport property:
Was Laredo okay with letting ASOS report VCTS CLR at 2356Z, since radar showed most of the level 6 thunderstorm was over Mexico?
7 lightning strikes hit within 5 miles. ALDARS at Laredo reported VCTS, when TS was warranted.
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Post by tornado on Mar 15, 2016 15:40:12 GMT -5
876. Monroe County Airport, Bloomington, Indiana, 19 (20) Jun 2015:
Bloomington (KBMG) recorded TS early on the 19th:
METAR KBMG 191253Z 31004KT 1/2SM +TSRA FG FEW006 BKN019 OVC029 20/19 A3005 RMK AO2 LTG DSNT SW TSB27 SLP170 P0072 T02000194
Later in the day, VCTS was recorded:
METAR KBMG 192053Z 09009KT 10SM SCT017 25/21 A2992 RMK AO2 SLP125 60000 T02500211 56024
METAR KBMG 192153Z 07008KT 10SM SCT016 SCT025 BKN033 24/21 A2992 RMK AO2 LTG DSNT SW AND W SLP125 T02390211
METAR KBMG 192253Z 07005KT 10SM -RA SCT026 SCT050 BKN080 23/21 A2992 RMK AO2 LTG DSNT S RAB45 SLP124 P0000 T02330206
SPECI KBMG 192313Z 08006KT 9SM VCTS -RA SCT018 BKN027 OVC110 23/21 A2992 RMK AO2 LTG DSNT ALQDS P0001 T02330211
SPECI KBMG 192334Z 12003KT 4SM VCTS +RA BR SCT018 BKN031 OVC110 23/21 A2991 RMK AO2 LTG DSNT SE-SW P0006 T02280211
METAR KBMG 192353Z 09005KT 7SM VCTS RA FEW018 FEW050 BKN110 23/21 A2991 RMK AO2 LTG DSNT E-SW SLP120 P0010 60010 T02280211 10256 20228 58003
SPECI KBMG 200034Z 14006KT 3SM VCTS +RA BR BKN013 BKN028 OVC060 22/21 A2991 RMK AO2 LTG DSNT E-SW CIG 006V020 P0016 T02220211
SPECI KBMG 200038Z 12006KT 2 1/2SM VCTS +RA BR SCT013 BKN028 OVC048 22/21 A2991 RMK AO2 LTG DSNT E-SW P0021 T02220211
SPECI KBMG 200046Z 16007KT 2 1/2SM VCTS +RA BR BKN010 BKN019 OVC050 22/21 A2992 RMK AO2 LTG DSNT E-SW P0027 T02220211
SPECI KBMG 200049Z 14009KT 3SM VCTS +RA BR FEW007 BKN013 OVC046 22/21 A2992 RMK AO2 LTG DSNT E-SW P0029
METAR KBMG 200053Z 12011G16KT 3SM VCTS +RA BR FEW007 BKN013 OVC046 22/22 A2991 RMK AO2 LTG DSNT E-SW SLP122 P0032 T02220217
SPECI KBMG 200055Z 12011KT 2 1/2SM +RA BR BKN009 BKN017 OVC046 22/21 A2991 RMK AO2 LTG DSNT E-SW P0003 T02220211
SPECI KBMG 200059Z 11010KT 2 1/2SM +RA BR FEW007 BKN035 OVC050 22/21 A2991 RMK AO2 LTG DSNT E AND S P0007 T02220211
SPECI KBMG 200110Z 11009KT 5SM RA BR SCT009 BKN050 OVC070 22/21 A2991 RMK AO2 LTG DSNT S P0011 T02220211
METAR KBMG 200153Z AUTO 15009KT 5SM RA BR FEW020 BKN100 OVC120 22/21 A2991 RMK AO2 SLP122 P0024 T02170206
It was during that lengthy VCTS, that there was a lightning issue:
4 lightning bolts struck within 5 miles of KBMG. No TS was recorded for those strikes, even though the closest bolt struck about 2,000 feet south of
airport property:
During part of the time VCTS was recorded, TS was warranted.
877. Crystal Airport, Minneapolis, Minnesota, 20 Jun 2015:
Crystal Airport (KMIC) had turned its ALDARS off overnight, in the pre-dawn hours of 20 Jun. Some weather rolled in:
METAR KMIC 200753Z AUTO 19014G20KT 10SM CLR 23/13 A2978 RMK AO2 SLP079 T02330133 TSNO
METAR KMIC 200853Z AUTO 15006KT 10SM BKN090 OVC120 22/15 A2977 RMK AO2 RAB30E50 SLP075 P0001 60001 T02170150 56012 TSNO
METAR KMIC 200953Z AUTO 12004KT 10SM OVC100 21/16 A2976 RMK AO2 RAB17E47 SLP074 P0001 T02060161 TSNO
SPECI KMIC 201042Z AUTO VRB03KT 1 3/4SM +RA BR SCT036 BKN055 OVC085 19/17 A2981 RMK AO2 RAB23 P0016 T01940172 TSNO
METAR KMIC 201053Z AUTO 12007KT 3SM RA BR FEW031 BKN038 OVC060 19/17 A2978 RMK AO2 RAB23 SLP079 P0023 T01890167 TSNO
During the period when ALDARS was disabled at KMIC, there was lightning that met both TS and VCTS criteria:
 
None of that lightning got reported, as ASOS was in TSNO mode. Weather observers and forecasters like to look “upstream” at other stations’ reports, to see what is heading their way. It can help formulate both TAFS and METARs. In this case, KMSP could have benefitted from accurate thunderstorm information. But that practice isn’t aided by sites that turn off ALDARS at night, thereby missing thunderstorms.
878. Martinsburg, West Virginia, 20 (21) Jun 2015:
Martinsburg (KMRB) is a level D site, that is not required to report thunderstorms. LAWRS observers signed off ASOS, placing it into AUTO/TSNO mode; then some bad weather hit:
METAR KMRB 202253Z AUTO 22007KT 6SM -RA FEW055 SCT080 BKN100 27/23 A2985 RMK AO2 RAB42 SLP101 P0001 T02720228 TSNO
SPECI KMRB 202303Z AUTO 26013G25KT 1 3/4SM +RA FEW017 SCT031 BKN050 23/20 A2982 RMK AO2 P0018 T02280200 TSNO
SPECI KMRB 202309Z AUTO 27013G21KT 1SM +RA BR BKN025 BKN050 BKN090 22/20 A2983 RMK AO2 WSHFT 2254 P0029 T02220200 TSNO
SPECI KMRB 202317Z AUTO 24009KT 3/4SM +RA BR FEW006 BKN021 OVC050 22/21 A2982 RMK AO2 WSHFT 2254 P0058 T02220206 TSNO
SPECI KMRB 202324Z AUTO 21007G16KT 1 1/4SM RA BR FEW006 BKN031 OVC048 22/21 A2983 RMK AO2 WSHFT 2254 P0062 T02220211 TSNO
SPECI KMRB 202340Z AUTO 19007KT 130V280 3SM -RA BR FEW006 BKN033 OVC100 22/21 A2982 RMK AO2 WSHFT 2254 P0073 T02220206 TSNO
METAR KMRB 202353Z AUTO 13007KT 10SM SCT009 BKN039 OVC120 22/21 A2983 RMK AO2 WSHFT 2254 RAE52 SLP096 P0073 60074 T02220206 10294 20222 56010 TSNO
METAR KMRB 210053Z AUTO 00000KT 10SM FEW048 BKN070 OVC090 22/21 A2981 RMK AO2 SLP089 T02220211 TSNO
Bad weather struck between 6-9 p.m., or 2200-0100Z Saturday evening. Martinsburg tower is listed as being open from 1300-2100 EDT on Saturdays, so why wasn’t a LAWRS observer signed on to ASOS during the above time period? That would have been the last 3 hours of operation for the day. Why did LAWRS sign off? Could it be so they didn’t have to deal directly with the weather, and let ASOS handle it? That would only make sense if ALDARS had remained enabled, and so detected this:
But KMRB remained logged off ASOS, during that time.
Right before the worst weather struck, KMRB was still logged off ASOS when they should have been logged on; with this on radar:
There is sometimes so much lightning around level D sites, that it makes no sense that thunderstorms aren’t required to be reported at such sites. See next case.
879. Easton, Maryland, 20 (21) Jun 2015:
Easton (KESN) is also a level D site. On the evening of the 20th (21st UTC), Easton reported some heavy rain; but only after LAWRS signed off, and only after missing METARs:
METAR KESN 202250Z 19008KT 10SM SCT030 SCT045 30/24 A2990
METAR KESN 202350Z NIL
METAR KESN 210050Z NIL
METAR KESN 210150Z NIL
METAR KESN 210159Z AUTO 18008KT 10SM RA BKN012 BKN024 27/24 A2990 RMK AO2 P0001 T02690239
METAR KESN 210216Z AUTO 16008KT 10SM -RA SCT009 BKN014 BKN024 26/24 A2989 RMK AO2 P0001 T02630242
METAR KESN 210236Z AUTO 23015G27KT 3SM +RA SCT005 SCT008 OVC013 25/23 A2995 RMK AO2 P0016 T02460231
METAR KESN 210256Z AUTO 19009KT 5SM RA BKN007 OVC014 23/23 A2992 RMK AO2 P0037 60038 T02290229
METAR KESN 210316Z AUTO 18007KT 10SM RA SCT009 BKN016 OVC020 23/23 A2990 RMK AO2 P0004 T02250225
This case is different than #878 from KMRB, because ASOS wasn’t placed into TSNO mode. Yet, ALDARS still missed the lightning:
There were 24 lightning strikes within 5 miles, that went unreported. Some of it was very close to the airport:
Yet, the FAA finds this a safe and acceptable practice: to allow D level LAWRS sites, not to report thunderstorms. LAWRS is the program that the FAA would like to replace the CWO program; keep in mind the “L” in LAWRS, stands for “Limited”.
880. Burlington, Iowa, 20 (21) Jun 2015:
D level site Burlington (KBRL) had an interesting case, even though it successfully reported a thunderstorm- for awhile. Firstly, here are the reports from KBRL, leading up to the thunderstorm:
METAR KBRL 202153Z AUTO 19016G24KT 10SM CLR 29/23 A2977 RMK AO2 SLP075 T02940228
METAR KBRL 202253Z AUTO 19014G17KT 10SM CLR 29/24 A2973 RMK AO2 SLP063 T02940239 METAR KBRL 202353Z AUTO 16005KT 10SM BKN032 BKN046 28/23 A2976 RMK AO2 SLP071 T02830233 10300 20267 55011
SPECI KBRL 210025Z AUTO 16008KT 10SM VCTS -RA FEW090 28/24 A2972 RMK AO2 LTG DSNT SW-N RAB17 PRESFR P0000 T02780239
SPECI KBRL 210040Z AUTO 14006KT 9SM -TSRA FEW037 SCT060 BKN100 27/24 A2972 RMK AO2 LTG DSNT SW-N RAB17 TSB34 P0001 T02720239
So at 7:34 p.m., Burlington began the thunderstorm (report transmitted at 0040Z). This was the lightning display, up until 0040Z:
Notice what happened next:
METAR KBRL 210053Z NIL
METAR KBRL 210153Z NIL
METAR KBRL 210253Z NIL
METAR KBRL 210353Z NIL
METAR KBRL 210453Z NIL
METAR KBRL 210553Z NIL
METAR KBRL 210653Z NIL
METAR KBRL 210753Z AUTO A2985 RMK AO2 RAB0617 TSB0634E0656 SLPNO PWINO $
METAR KBRL 210853Z AUTO A2986 RMK AO2 SLPNO 6//// PWINO $
METAR KBRL 210953Z AUTO A2987 RMK AO2 SLPNO PWINO $
METAR KBRL 211053Z AUTO A2990 RMK AO2 SLPNO PWINO $
METAR KBRL 211153Z AUTO A2993 RMK AO2 SLPNO 6//// 7//// 53023 PWINO $
METAR KBRL 211253Z AUTO A2995 RMK AO2 SLPNO PWINO $ METAR KBRL 211354Z AUTO A2996
METAR KBRL 211453Z AUTO A2998
METAR KBRL 211553Z AUTO A2996 RMK AO2 SLPNO PWINO $
METAR KBRL 211653Z AUTO A2999 RMK AO2 SLPNO PWINO $
METAR KBRL 211753Z AUTO A2996
METAR KBRL 211853Z AUTO A2997 RMK AO2 SLPNO PWINO $
METAR KBRL 211953Z AUTO A2995 RMK AO2 SLPNO PWINO $ METAR KBRL 212053Z AUTO 21012KT 10SM CLR 27/23 A2995 RMK AO2 SLPNO T02670233 58004 $
Observations were missing for 7 hours; then, ASOS returned to service for 1 report at 0753Z, after which there was much missing data for several hours. Why did that happen?
Notice how much lightning struck the Burlington area, in just 20 minutes! For that 20-minute period, there was CONS LTGCG near KBRL:
No reports were transmitted from KBRL, between 0040Z and 0753Z. The 0753Z METAR remarked that a thunderstorm began at 0634Z. So, was there any lightning within 10 miles of KBRL, between 0040-0600Z? Yes:
The above map is set to end at 0400Z. It shows plenty of lightning was still striking within 10 miles of KBRL, after lightning apparently put ASOS out of commission. That means ASOS didn’t report lightning, after a probable lightning strike!
If this sort of thing can happen at a D level site, what prevents it from happening at an A level site? At least right now, A and B level sites have a back up system in place- the Contract Weather Observer.
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Post by tornado on Mar 17, 2016 13:58:51 GMT -5
881. Newport News, Virginia, 20-21 Jun 2015:
Between 0200-0500Z on 21 Jun (part of that time was the 20th, EDT) Newport News-Williamsburg International Airport (KPHF) had a lot of lightning in the area:
Was that reported?
METAR KPHF 210154Z 17019G25KT 10SM CLR 32/22 A2985
METAR KPHF 210254Z 19013G25KT 10SM CLR 31/23 A2984 RMK AO2 LTG DSNT SW-N SLP103
T03060228 58009
METAR KPHF 210354Z NIL
METAR KPHF 210454Z NIL
METAR KPHF 210554Z NIL
METAR KPHF 210654Z NIL
METAR KPHF 210754Z NIL
METAR KPHF 210854Z AUTO 24013G21KT 10SM CLR 28/24 A2981 RMK AO2 SLP092 6////
T02830239 $
There wasn’t a report of a thunderstorm, transmitted from KPHF; because there were 5 missing METARs, possibly due to the thunderstorm itself. For, when zooming in on the data, it can be seen that the airport took at least 3 lightning strikes:
Possibly as many as 5 lightning bolts struck the airport. That map is valid for he most active 5-minute period, between 0330-0335Z. Now, here is a diagram of Newport News-Williamsburg International Airport, with the control tower outlined in red:
1 lightning bolt that struck just west of airport property, was closer to the control tower, than the bolts that struck on airport property. Its distance from the tower can be measured:
On the insert map to the right, the bolt whose distance is being measured, is the bolt plotted in blue, just west of the small airport icon. The distance from the lightning strike, to the control tower, appears to have been about 769 feet! It’s not unreasonable to believe that one of the other lightning bolts to strike the airport, took out ASOS.
97 lightning strikes within 5 miles, went unreported; with about another 150 strikes between 5-10 miles going unreported! That an approximate total of 247 lightning strikes within 10 miles. LAWRS was signed on to ASOS at 0254Z, at which time ALDARS reported LTG DSNT SW-N. At that time, a line of strong thunderstorms was bearing down on Newport News:
The line reached Newport News by 0325Z:
So, how many of the 247 lightning strikes within 10 miles, hit prior to 0325Z? Let’s look at that:
Lightning as close as 6 miles to the SW, struck before 0325Z. Why didn’t ALDARS (which was installed at this site on 13 Dec 2000) start VCTS? The orange lightning plot in Burwell Bay, about 8.5 miles to the SW; also met VCTS criteria, and struck about 0316Z. But before ASOS and ALDARS could report lightning, lightning knocked ASOS/ALDARS off the air! If that can happen at a level C site, what prevents that from happening at an A level site?
882. Central Illinois Regional Airport, Bloomington-Normal, Illinois, 20-21 Jun 2015:
Bloomington-Normal (KBMI) reported VCTS around midnight of the 20-21st of June:
METAR KBMI 210156Z 20009KT 10SM CLR 24/21 A2983 RMK AO2 T02440211 SLP089
METAR KBMI 210256Z 18011KT 10SM VCTS CLR 24/21 A2982 RMK AO2 58001 T02440211 TSB51 SLP085
METAR KBMI 210356Z NIL
METAR KBMI 210456Z NIL
SPECI KBMI 210529Z AUTO 17016KT 6SM -RA BR BKN001 BKN032 BKN046 21/20 A2987 RMK AO2 TSNO BKN V SCT P0007 WSHFT 0509
So while VCTS got reported; the same thing happened at KBMI, as happened that night at KPHF: METARs went missing for a time, possibly due to lightning. For the lightning data showed strikes were closer than just VCTS criteria:
Zooming in on the data, shows strikes to the airport, including possible lightning strikes to both runways 2/20 and 11/29:
The 0256Z METAR containing VCTS, was at 9:56 p.m. The control tower closed at 10 p.m. The first lightning strike at the airport, was about 10:06 p.m.:
After that bolt struck, no reports were transmitted from KBMI, until 12:29 a.m. on the 21st. The other 2 bolts struck just prior to 10:35 p.m.:
At 0315Z, radar recorded that a level 6 cell was over the airport:
Conditions were no longer VCTS CLR, and a SPECI should have been taken to show +TSRA. But by then, ASOS was malfunctioning. 2 cases in a row, had unreported TS conditions, due to lightning strikes at an airport.
883. McKinney, Texas, 21 Jun 2015:
For several reports on 21 Jun, McKinney (KTKI) recorded VCTS:
METAR KTKI 211053Z 15006KT 10SM FEW016 BKN090 OVC110 23/21 A3004 RMK AO2 SLP168 T02280211
METAR KTKI 211153Z 12006KT 10SM VCTS OVC016 23/22 A3003 RMK AO2 LTG DSNT SE AND S SLP164 70013 T02330217 10233 20222 50004
SPECI KTKI 211207Z 12008KT 10SM VCTS OVC014 23/22 A3003 RMK AO2 LTG DSNT E-S T02330217
SPECI KTKI 211248Z 10009KT 9SM VCTS -RA FEW005 BKN012 OVC027 23/22 A3004 RMK AO2 LTG DSNT E-S RAB39 P0000
METAR KTKI 211253Z 12009G16KT 10SM VCTS FEW005 BKN018 OVC027 23/22 A3004 RMK AO2 LTG DSNT E-S RAB39E49 SLP169 P0000 T02280217
SPECI KTKI 211316Z 13007KT 1 3/4SM VCTS +RA BR BKN017 OVC021 22/22 A3006 RMK AO2 LTG DSNT NE-S RAB1255 P0011 T02220217
METAR KTKI 211353Z 17013KT 2SM VCTS +RA BR BKN017 OVC030 23/22 A3007 RMK AO2 LTG DSNT ALQDS RAB1255 SLP178 P0067 T02280222
SPECI KTKI 211400Z 17013KT 2 1/2SM VCTS +RA BR BKN012 BKN021 OVC036 23/22 A3007 RMK AO2 LTG DSNT N-SE P0008 T02330222
SPECI KTKI 211414Z 15009KT 6SM VCTS -RA BR BKN012 BKN021 OVC036 23/22 A3007 RMK AO2 LTG DSNT N-SE P0012 T02330222
SPECI KTKI 211440Z 15010KT 3SM VCTS +RA BR FEW008 BKN013 OVC027 23/23 A3008 RMK AO2 LTG DSNT NE AND E P0021 T02330228
METAR KTKI 211453Z 16009KT 5SM VCTS -RA BR BKN004 BKN009 OVC029 23/23 A3008 RMK AO2 LTG DSNT NE SLP184 P0023 60090 T02330228 53014
SPECI KTKI 211456Z 16008KT 2 1/2SM VCTS -RA BR BKN006 BKN012 OVC029 23/23 A3008 RMK AO2 LTG DSNT N AND NE P0001 T02330228
SPECI KTKI 211512Z 15010KT 2 1/2SM VCTS -RA BR BKN004 OVC012 23/23 A3006 RMK AO2 LTG DSNT N-SE P0004 T02330228
METAR KTKI 211553Z 12005KT 3SM -RA BR OVC004 23/23 A3008 RMK AO2 LTG DSNT W-NE SLP182 P0006 T02330228
SPECI KTKI 211626Z 11005KT 6SM VCTS -RA BR OVC006 24/23 A3008 RMK AO2 LTG DSNT N AND NE CIG 004V009 P0001 T02390228
METAR KTKI 211653Z 15005KT 7SM OVC007 24/23 A3008 RMK AO2 RAE45 SLP183 P0001 T02390233
METAR KTKI 211750Z 12006KT 6SM BR BKN017 BKN038 OVC100 24/24 A3007 RMK AO2 LTG DSNT N RAB11E30 P0000
So while VCTS was recorded, TS was not. One would therefore not expect to see any lightning within 5 miles of McKinney, on a lightning plot map:
Yet, while ALDARS successfully reported the lightning that struck between the red and green range rings; none of the lightning that struck within the red 5-mile range ring, was reported at all! That numbered 36 bolts. Zooming in shows how close the bolts struck:
One lightning bolt struck the northern end of runway 17/35! Another struck the field just east of the runway. That’s certainly not what a VCTS describes!
The lightning strike to the runway, occurred about 1207Z:
There was a SPECI right at 1207Z, but ASOS did not take another SPECI for TS; and did not take another SPECI until 1248Z:
SPECI KTKI 211207Z 12008KT 10SM VCTS OVC014 23/22 A3003 RMK AO2 LTG DSNT E-S T02330217
SPECI KTKI 211248Z 10009KT 9SM VCTS -RA FEW005 BKN012 OVC027 23/22 A3004 RMK AO2 LTG DSNT E-S RAB39 P0000
Also, that lightning strike, came at a time when it was not raining at McKinney. The core of the thunderstorm producing the lightning, was about 7 miles to the SE, and was returning level 5 rain echoes:
Hazards associated with thunderstorms, can strike under or near the parent cell; as this case is one of several that documents those conditions. Judging by the first few reports containing VCTS, there weren’t any hazards within 5 miles. It wasn’t until 1316Z, that VCTS with heavy rain, made the field IFR due to 1.75 miles visibility. But as early as 1245Z, hazards were certainly within 5 miles of the airport:
McKinney tower opened at 6:00 a.m., or 1100Z that Sunday morning. The strike to the airport came just over an hour after the control tower opened. ALDARS failed to detect or range that lightning properly; and LAWRS didn’t override ALDARS as being unrepresentative. Therefore, VCTS was carried at a time when TS was justified.
884. Downtown Airport, Kansas City, Missouri, 21 Jun 2015:
Kansas City-Downtown Airport (KMKC) recorded VCTS on the 21st:
METAR KMKC 211354Z 23013KT 10SM CLR 27/22 A2990 RMK AO2 LTG DSNT NW-NE SLP115 T02670222
SPECI KMKC 211413Z 23011G18KT 10SM VCTS FEW024 SCT100 BKN120 27/22 A2993 RMK AO2 LTG DSNT W-NE PRESRR T02720217
METAR KMKC 211454Z 00000KT 10SM VCTS FEW060 FEW075 BKN100 27/22 A2994 RMK AO2 LTG
DSNT NW-E SLP128 T02670222 53015
SPECI KMKC 211504Z 20006KT 10SM FEW060 SCT110 27/22 A2992 RMK AO2 LTG DSNT NW-E T02670222
METAR KMKC 211554Z 00000KT 10SM OVC065 27/23 A2992 RMK AO2 LTG DSNT NW-E SLP123 T02670228
SPECI KMKC 211602Z 00000KT 10SM VCTS OVC070 27/23 A2993 RMK AO2 LTG DSNT NW-E T02670228
METAR KMKC 211654Z 05012KT 10SM VCTS BKN030 OVC070 26/23 A2995 RMK AO2 LTG DSNT N-E SLP134 T02610228
SPECI KMKC 211741Z 09005KT 10SM BKN036 BKN075 24/21 A2995
METAR KMKC 211754Z VRB03KT 10SM FEW038 BKN075 BKN090 24/21 A2996 RMK AO2 LTG DSNT
NW-E SLP135 T02390211 10278 20233 53006
So again, checking for lightning within 5 miles of the airport, reveals this:
There were 4 lightning strikes within 5 miles of KMKC, that met TS criteria; TS wasn’t reported during the valid time of the lightning map. Yet one of those bolts struck the northern end of runway 1/19:
Lightning strikes were plotted in blue and red, meaning there were 2 separate thunderstorms. VCTS was recorded twice during that 4-hour period. Isolating the time of the red plot- the bolt that struck runway 1/19- shows it hit about 1638Z:
Why would a lightning strike at an airport, about a mile north of the control tower; be reported as VCTS instead of TS? Both ALDARS and LAWRS would have to miss that lightning for that to happen.
885. McAllen, Texas, 21 Jun 2015:
McAllen (KMFE) recorded VCTS between 1722-1853Z:
METAR KMFE 211653Z 15015G26KT 10SM CLR 34/24 A2999 RMK AO2 PK WND 13028/1625 LTG DSNT S RAB1559E10 SLP154 P0000 T03390244
SPECI KMFE 211722Z 13023G27KT 10SM VCTS SCT036 BKN043 BKN055 34/24 A2999 RMK AO2 PK WND 12027/1721 LTG DSNT S AND SW T03390244
SPECI KMFE 211748Z 17022G34KT 1 1/2SM VCTS +RA FEW011 BKN043 OVC070 25/22 A3004 RMK AO2 PK WND 17034/1740 LTG DSNT SE-W RAB40 P0007
METAR KMFE 211753Z 18016G29KT 3/4SM VCTS +RA BR FEW010 BKN034 OVC075 24/22 A3004
SPECI KMFE 211805Z 17011G22KT 2SM VCTS RA BR FEW010 BKN034 BKN070 24/22 A3002 RMK AO2 LTG DSNT ALQDS PRESFR P0008 T02440222
SPECI KMFE 211813Z 14014KT 6SM -RA SCT034 SCT070 BKN110 25/22 A3002 RMK AO2 LTG DSNT ALQDS P0008 T02500222
SPECI KMFE 211832Z 14010KT 10SM VCTS FEW120 25/22 A3003 RMK AO2 LTG DSNT ALQDS RAE31 P0008 T02500217
METAR KMFE 211853Z 15009KT 9SM -RA FEW120 25/22 A3001 RMK AO2 LTG DSNT N AND NW RAE31B39 SLP161 P0008 T02500222
So was the heavy rain, due to a thunderstorm 5-10 miles from McAllen, or was there lightning closer than that?
According to the lightning data above, there were 8 bolts that struck within 5 miles of KMFE during that time period. TS was not reported. Lightning struck as near as 3 miles away:
KMFE reported VCTS, at a time when TS was warranted.
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Post by tornado on Mar 17, 2016 15:24:05 GMT -5
886. Olive Branch, Mississippi, 21 Jun 2015:
Between 1900-2000Z on the 21st, Olive Branch (KOLV), which is a D level site just SE of Memphis; recorded a thunderstorm in the vicinity (VCTS):
METAR KOLV 211850Z 25009G14KT 10SM FEW035 SCT150 BKN250 32/25 A3008
METAR KOLV 211950Z 27014G18KT 10SM VCTS BKN036 BKN250 31/24 A3008
METAR KOLV 212050Z 26009G15KT 10SM FEW035 SCT150 BKN250 31/22 A3007
However, lightning data reveals 4 strikes that hit within 5 miles of the airport:
The nearest of those bolts, struck less than 2 miles to the SE:
ALDARS at KOLV reported a VCTS, at a time when it should have reported TS.
887. Laredo, Texas, 21 Jun 2015:
Between 1900-2100Z, Laredo (KLRD) reported some light rain, and gusty winds:
METAR KLRD 211856Z 15018G22KT 10SM FEW001 SCT042 SCT075 33/23 A2996 RMK AO2 T03330227 SLP134
METAR KLRD 211956Z 14014G19KT 10SM SCT041 BKN055 34/23 A2993 RMK AO2 T03440233 BKN V SCT SLP122
METAR KLRD 212056Z 14011KT 10SM -RA CLR 26/23 A2994 RMK AO2 55015 60000 T02550233 RAB07 P0000 PK WND 14037/2011 SLP127
What wasn’t reported, was any lightning or thunder:
During that 2-hour period, there were 21 lightning bolts that struck within 10 miles of KLRD; with 4 of those also striking within 5 miles of the airport. The nearest bolt struck about 2 miles to the NNE:
Around 2000Z, KLRD had an unreported thunderstorm. Which was strange, considering that, after LAWRS went home for the evening at 8 p.m. CDT (0100Z), ASOS immediately reported a thunderstorm:
SPECI KLRD 220106Z AUTO 20018G23KT 10SM TSRA FEW014 BKN020 OVC030 24/22 A3001 RMK AO2 LTG DSNT ALQDS TSB00 P0000
SPECI KLRD 220136Z AUTO 14016G23KT 2 1/2SM +TSRA BR FEW002 BKN011 OVC032 23/22 A3003 RMK AO2 LTG DSNT ALQDS TSB00 P0000 WSHFT 0101
The worst conditions were at 8:36 p.m.; but TSB00 means that ALDARS detected lightning within 5 miles of KLRD, and triggered ASOS to take the 0106Z SPECI. SO why wasn’t the previous thunderstorm reported? Did LAWRS turn off ALDARS as being unrepresentative, yet not back up ASOS for lightning?
888. Brookley Field Airport, Mobile, Alabama, 21 Jun 2015:
Brookley Field (KBFM) in Mobile had a thundery day after 1800Z:
METAR KBFM 211753Z 12008KT 10SM SCT036 32/25 A3013 RMK AO2 SLP202 60000 T03220250 10333 20267 58010
METAR KBFM 211853Z 14009KT 10SM SCT036 33/26 A3011 RMK AO2 LTG DSNT S AND SW SLP196 TCU DSNT S T03280261
SPECI KBFM 211903Z 15008KT 10SM VCTS SCT035 32/26 A3011 RMK AO2 LTG DSNT S AND SW T03220256
METAR KBFM 211953Z VRB05KT 10SM -RA FEW035 SCT075 32/24 A3009 RMK AO2 RAB50 SLP188 TCU DSNT SW P0000 T03220244
SPECI KBFM 212014Z 22006KT 10SM VCTS FEW035 SCT075 32/22 A3008 RMK AO2 RAE05 TCU DSNT SW P0000 T03170217
SPECI KBFM 212042Z 21008KT 10SM SCT035 32/23 A3007 RMK AO2 RAE05 TCU DSNT SW P0000 T03220228
METAR KBFM 212053Z 20008KT 10SM SCT035 32/22 A3007 RMK AO2 RAE05 SLP183 TCU DSNT SW-N P0000 60000 T03220222 56018
METAR KBFM 212153Z 23007KT 10SM FEW037 32/24 A3007 RMK AO2 LTG DSNT W SLP182 CB DSNT W TCU DSNT W-N T03220244
SPECI KBFM 212234Z VRB04KT 10SM VCTS SCT035CB 32/24 A3007 RMK AO2 LTG DSNT W-NE CB N MOV SE CB DSNT W TCU DSNT E AND NW T03220239
METAR KBFM 212253Z COR 23007KT 10SM VCTS SCT035CB 31/23 A3007 RMK AO2 LTG DSNT NW-NE SLP181 CB NW-NE MOV SE CB DSNT E AND W TCU DSNT W-NW T03110233
SPECI KBFM 212303Z 24006KT 10SM TS SCT033CB 31/23 A3006 RMK AO2 LTG DSNT W-NE TSB2257 CB N-NE MOV SE TCU DSNT W-NW T03060233
So at 2257Z, a thunderstorm finally moved or formed within 5 miles of Brookley Field. Prior to that, VCTS was reported, which meant lightning was detected 5-10 miles from the airport. However, lightning data showed this:
Well before 2250Z, 5 lightning bolts struck within 5 miles of KBFM. The plots, some being in purple and some being in yellow, represent 2 separate thunderstorms. While the newer storm had its lightning plotted in yellow, all of which were beyond 5 miles; the older storm’s lightning, plotted in purple, was the one which met TS criteria. One of those bolts struck not long after 1900Z, and hit State Highway 163 about 3,000 feet from airport property:
That’s about a half mile away from the airport. Such lightning is not classified as VCTS, but TS. Yet only VCTS was reported at KBFM until about 3 hours later.
889. Naples, Florida, 21 Jun 2015:
Just after 2200Z, ALDARS at Naples (KAPF) appeared to be working fine:
SPECI KAPF 212201Z 26013G19KT 7SM -TSRA FEW032 BKN055 OVC075 31/26 A3004 RMK AO2 LTG DSNT SE AND S RAB2158 TSB2155 P0001 T03060261
METAR KAPF 212253Z 00000KT 10SM VCTS FEW060 SCT090 BKN110 29/24 A3005 RMK AO2 LTG DSNT ALQDS RAB2158E11 TSB2155E53 SLP173 P0001 T02890239
But between 21/2300Z-22/0000Z, no thunder was recorded, as the VCTS was ended right at 2300Z:
SPECI KAPF 212300Z 00000KT 10SM FEW060 FEW090 SCT110 29/24 A3004 RMK AO2 LTG DSNT N AND S AND NW T02890239
METAR KAPF 212353Z 17009KT 10SM CLR 29/24 A3006 RMK AO2 LTG DSNT SW-N SLP176 60001 T02940244 10333 20289 53004
Yet, there was still lightning within 10 miles of KAPF, during that hour:
There were 4 lightning strikes which met VCTS criteria, and 2 which met TS criteria. The closest strike occurred about a mile north of the airport:
Actually, the strike was less than a mile north of airport property, and about 1 mile north of where runways 5/23 and 14/32 cross. Yet, even though both TS and VCTS had been recorded in the previous 2 hours, the bolt which struck a mile away at about 2346Z, triggered no TS. That means ALDARS is unreliable, as it is sometimes successful at detecting lightning, while at other times unsuccessful at doing so. The problem is knowing when to trust ALDARS!
890. Hector International Airport, Fargo, North Dakota, 22 Jun 2015:
From midnight to 2 a.m. on June 22nd, Fargo (KFAR) had some heavy rain, with gusty and shifting winds:
METAR KFAR 220453Z 14017G22KT 10SM -RA BKN080 OVC100 24/14 A2969 RMK AO2 RAB49 SLP048 P0000 T02390139
METAR KFAR 220553Z 16015KT 6SM RA SCT065 BKN080 OVC110 21/17 A2973 RMK AO2 PRESRR SLP064 P0009 60009 T02110172 10272 20211 402940111 55003
SPECI KFAR 220603Z 28023G26KT 1 3/4SM +RA BR FEW016 BKN060 OVC110 19/17 A2977 RMK AO2 PK WND 28026/0602 WSHFT 0547 PRESRR P0010 T01890167
SPECI KFAR 220611Z 21020G38KT 1SM +RA BR FEW018 BKN026 OVC090 18/17 A2978 RMK AO2 PK WND 27038/0606 WSHFT 0552 P0023 T01830167
SPECI KFAR 220620Z 21016G27KT 2 1/2SM -RA BR BKN027 OVC090 19/17 A2975 RMK AO2 PK WND 27038/0606 WSHFT 0606 P0038 T01890172
SPECI KFAR 220627Z 22012KT 10SM -RA FEW015 BKN080 OVC100 19/17 A2975 RMK AO2 PK WND 27038/0606 WSHFT 0606 P0038 T01890172
METAR KFAR 220653Z 21005KT 9SM -RA BKN090 OVC110 19/17 A2974 RMK AO2 PK WND 27038/0606 WSHFT 0606 SLP066 P0040 T01890172
Notice no lightning nor thunder was recorded. The data shows that LTG and TS should have been reported:
Of the 24 bolts that struck within 10 miles of KFAR, 4 also struck within the red 5-mile range ring around KFAR. The nearest cloud-to-ground lightning was about 2 miles NW of the runways, or 1 mile from airport property:
Hector Intl Airport had an unreported pre-dawn thunderstorm that day.
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Post by tornado on Mar 18, 2016 11:44:12 GMT -5
891. Lakeland, Florida, 22 Jun 2015:
Lakeland (KLAL) is a D level site, that reported a thunderstorm on the 22nd:
METAR KLAL 230150Z 08007KT 10SM TS BKN050 29/24 A3013 RMK OCNL LTG CG TSB50 TS E MOV W LAST
That was the last METAR that LAWRS put out, at 9:50 p.m., before the tower closed. However, between 1700-1900Z, there was another thunderstorm near Lakeland, that didn’t get reported:
Here were the reports from that time:
METAR KLAL 221650Z 00000KT 10SM SCT035 32/24 A3012
METAR KLAL 221750Z 21003KT 10SM VCSH SCT035 33/24 A3012
METAR KLAL 221850Z 28011G16KT 10SM SCT065 31/24 A3011
So LAWRS entered VCSH into present weather at 1750Z. But what of the 51 lightning strikes that met VCTS criteria, or the 4 bolts that met TS criteria? Those weren’t reported in a METAR, nor was a SPECI taken to record VCTS or TS. Some of the lightning was a close as 3 miles away:
Why did one thunderstorm get reported- right before the tower closed for the night- and another thunderstorm around 2 p.m. go unreported?
892. Houma, Louisiana, 22 Jun 2015:
Houma (KHUM) is a D level site, that attempted to report a thunderstorm on the 22nd:
METAR KHUM 221847Z 16007KT 7SM SCT038 33/24 A3013 RMK ATIS O VA RY18 DV
METAR KHUM 221947Z 18008KT 7SM SCT042 33/24 A3012 RMK ATIS P VA RY18....DV TS NE MOV E LTG DSNT NE/SE
METAR KHUM 222047Z 27003KT 7SM SCT033 25/23 A3011 RMK ATIS R VA RY18....DV
So at 1947Z, a thunderstorm was reported in remarks. Thunderstorms are to have matching present weather entries, but this one didn’t. Also, the lightning was said to be distant, which would be defined as beyond 10 miles from the airport, but within 30 miles. Was the thunderstorm also distant? The remark TS NE is reported as such, only if the thunderstorm was within 5 miles of the airport. So the second issue, is that the remarks were contradictory. So what really happened? Here is the lightning plot map from 1900-2100Z on the 22nd, around Houma:
Yes, there was lightning within 5 miles- 20 such strikes. DSNT should not have been appended to the manual lightning remarks, unless TS was in present weather to signify there was also lightning within 5 miles. Also, that would only be the case if ALDARS detected and reported the lightning; here, it was the HWO that reported the lightning. Lightning striking this close to the airport, should have resulted in TS in present weather:
So a D level site, attempted to report a thunderstorm. The attempt was only partially correct.
893. Lakefront Airport, New Orleans, Louisiana, 22 Jun 2015:
D level sites like Houma aren’t required to report thunderstorms. However, C level are required to do so. Yet, up the road from Houma is Lakefront Airport (KNEW) in New Orleans; a C level site that missed reporting a thunderstorm on the 22nd.
Between 1800-2100Z, here was the lightning display around KNEW:
So there were 10 lightning strikes plotted that met VCTS criteria, and 3 lightning strikes that met TS criteria. How close was the nearest lightning strike?
 
One lightning bolt struck the SE part of the airport! That was east of an FBO, and south of a hangar, at about 1957Z. So what were the reports from KNEW around that time? Firstly, it’s unclear why ASOS at KNEW was in AUTO/TSNO mode at 1753Z, or 12:53 p.m. CDT:
METAR KNEW 221753Z AUTO 32006KT 10SM CLR 32/23 A3014 RMK AO2 SLP199 T03220233 10328 20283 57004 TSNO
METAR KNEW 221853Z 34007KT 10SM CLR 34/24 A3012 RMK AO2 SLP192 T03390239
METAR KNEW 221953Z 29010KT 10SM FEW047 33/24 A3011 RMK AO2 SLP189 T03280239
METAR KNEW 222053Z 23007KT 10SM FEW044 32/23 A3010 RMK AO2 SLP186 T03170228 56014
So 4 minutes after the 1953Z METAR was transmitted with 10SM FEW047 and no LTG remarks, lightning struck the airport. How was it that lightning so close, didn’t get reported? Was it because of the radar display?
At 1950Z, a level 5 cell was about 10 miles to the SW of KNEW; with a level 6 cell 18 miles to the WSW. The nearest rain echo was about 6 miles to the SW. Nevertheless, strong thunderstorms can produce lightning strikes well outside their associated rain shafts. This is a case of such a lightning strike. Even “dry thunderstorms” are to be reported; 10SM TS would have been fine in this case, but KNEW did not report that. Perhaps because radar rain echoes are relied upon, to determine where hazards exist; KNEW had an unreported thunderstorm on June 22nd.
By the way, the closest approach of that level 5 cell, to Lakefront Airport, was at 2035Z, when the core of the cell was 3 miles to the south.
Still no thunderstorm or even CB was reported. There wasn’t any lightning to the south during that period. So the lightning that struck the airport, came at a time when the cell was centered 10 miles away; at the time the level 5 cell was 3 miles away, it wasn’t producing lightning. Lightning and thunderstorms can be fickle; this is why they need to be properly reported!
894. Toledo Express Airport, Ohio, 22 Jun 2015:
Between 1900-2100Z on the 22nd, Toledo Express Airport (KTOL) transmitted 3 METARs and no SPECIs:
METAR KTOL 221852Z 22007KT 180V240 10SM SCT036 BKN047 BKN055 28/22 A2994 RMK AO2 SLP135 T02830222
METAR KTOL 221952Z 22010G19KT 10SM FEW033 SCT080 29/22 A2993 RMK AO2 SLP130 T02890217
METAR KTOL 222052Z 20007KT 10SM -RA FEW041 SCT100 SCT120 26/21 A2983 RMK AO2 RAB1959E23B47 SLP096 P0000 60000 T02560211 58045
Yet, lightning data showed strikes within 10 miles of KTOL during that period:
There were 25 strikes that met VCTS criteria, and 4 bolts that met TS criteria. The nearest strike was less than 2 miles to the NW:
Despite winds gusting to 19 knots, and a bit of light rain for clues; a thunderstorm went unreported at KTOL that day.
895. Stennis International Airport, Bay St. Louis, Mississippi, 22 Jun 2015:
Stennis International Airport (KHSA) is another D level site. Between 22/2100-23/0000Z, this was the lightning display around Bay St. Louis:
10 lightning bolts struck within the red 5-mile range ring around KHSA, meeting TS criteria. Another 19 strikes met VCTS criteria. Yet, those conditions were not required to be reported by this D level site, and it did not do so:
METAR KHSA 222051Z 21006KTS 7SM SCT045 33/21 A3008
METAR KHSA 222151Z 19006KTS 7SM SCT050 33/22 A3007
METAR KHSA 222251Z VRB04KTS 7SM SCT044 28/20 A3009
METAR KHSA 230051Z 00000KTS 7SM CLR 27/19 A3009
Lightning struck as close as 2 miles from the airport:
Compare the 2151Z METAR, to the 2150Z radar:
The 2151Z METAR is shown in the bottom right corner of the map. The level 6 cell about 6 miles to the NNW wasn’t mentioned. Why does the FAA consider this to be a safe practice: that thunderstorms aren’t required to be reported at D level sites?
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Post by tornado on Mar 18, 2016 14:38:01 GMT -5
896. Cecil Airport, Jacksonville, Florida, 22 (23) Jun 2015:
Late enough on 22 Jun, that it spilled over into the 23rd UTC; Cecil Airport (KVQQ) In Jacksonville had a lightning issue. This came after a thunderstorm was reported at around 3 a.m.:
SPECI KVQQ 220659Z VRB06KT 1 1/2SM +TSRA FEW004 BKN010CB OVC020 23/22 A3014 RMK RAB50 FRQ LTGICCA ALQDS TS OVHD MOV NE
After 11:30 p.m. that night, another thunderstorm was reported:
SPECI KVQQ 230339Z 13003KT 10SM -TSRA FEW020 SCT035CB BKN120 23/23 3020 RMK TSRAB39 FRQ LTGCGICCA VC E-S-SW TS VC E-S-SW MOV N
Yet, between those 2 thunderstorms, from 2300-0030Z, a thunderstorm wasn’t properly reported:
METAR KVQQ 222250Z 00000KT 10SM CLR 33/25 A3004
METAR KVQQ 222350Z 23014G19KT 5SM RA BKN030 29/22 A3009
SPECI KVQQ 230000Z 23014KT 2SM RA BKN009 27/23 A3010
SPECI KVQQ 230030Z 03006KT 5SM RA BKN020 23/23 A3011 TSE 30
The 0030Z SPECI claims in remarks, that a thunderstorm had just ended at 0030Z. Yet there was no thunderstorm reported in the previous SPECI at 0000Z, nor the METAR at 2350Z. Also, no thunderstorm beginning time (TSB) was recorded. So what happened between 2300-0030Z?
There certainly was a thunderstorm in progress during that time! 104 lightning bolts struck in the same grid in which the airport is located, all of those within 10 miles. At least 4 lightning bolts struck the airport complex:
Those 4 strikes actually hit between 22/2330-23/0000Z:
Yet, while 23014G19KT 5SM RA BKN030 was reported on the 2350Z METAR, there was no mention of LTG, TS, or even CB! The 0030Z SPECI ended a thunderstorm, that was never officially begun!
There were 60 lightning bolts that struck within 5 miles of the airport, prior to 0030Z. About 75 more strikes met VCTS criteria, for a total of 135 strikes within 10 miles. 4-6 bolts struck the airport itself, with 4 of those hitting prior to 0000Z. For all of this, a thunderstorm was not reported for that 90 minute period! Then, TSE30 was added on the 0030Z SPECI, as an aftersight; for TS did not appear in present weather or even in remarks, during the previous 90 minutes. Therefore, KVQQ had an unreported thunderstorm in the 90 minutes prior to 23/0030Z; even though the site reported 2 other thunderstorms that day.
897. Pascagoula, Mississippi, 22 (23) Jun 2015:
After 2200Z on the 22nd, Pascagoula (KPQL) had some benign-looking weather reports:
METAR KPQL 222153Z VRB06KT 10SM CLR 33/24 A3007 RMK AO2 SLP183 T03280244
METAR KPQL 222253Z 22007KT 10SM CLR 32/25 A3006 RMK AO2 SLP181 T03220250
METAR KPQL 222353Z 06011KT 8SM FEW032 BKN044 BKN055 26/18 A3011 RMK AO2 WSHFT 2332 PRESRR SLP199 T02610183 10344 20261 53016
METAR KPQL 230053Z NIL
METAR KPQL 230153Z AUTO A3008 RMK AO2 RAB00230054 SLP189 P0016 PWINO TSNO $
What wasn’t mentioned in any of those reports, was how much lightning had struck the area:
In the grid where the airport is located, 218 lightning bolts struck, with the vast majority of those hitting within 10 miles! Overall, it is estimated that 300 lightning bolts struck within 10 miles of KPQL. How is it that none of that got reported? The AMSS web site, lists Pascagoula as a C level site, with ALDARS enabled since 18 Apr 2000.
Even if KPQL had dropped to being a D level site, Table D-1 of the 7900.5C still would require it to report lightning; as D level sites with ALDARS are required to do:
Lightning as close as 1 mile from the airport, went unreported:
At 2340Z, a level 6 cell was nearby; its level 5 rain echoes stretched from 1-10 miles NE-E of the airport:
The 23/0153Z METAR reported TSNO in remarks. None of the others METARs quoted above, did so. That meant either ALDARS was enabled, and turned on until 0153Z; or ALDARS was turned off so that LAWRS observers could manually report the lightning. But the second possibility did not occur; and for the first possibility to occur, would mean that ALDARS missed 218 lightning strikes! Is there another possibility?
I went back through the records, and the last thunderstorm reported at KPQL, was on Thu 10 Jul 2014:
SPECI KPQL 101910Z 26004KT 1/2SM TSRA OVC031 22/21 A3012 RMK AO2 P0046 T02170211
That was the only thunderstorm reported at KPQL in 2014; there were zero thunderstorms reported at KPQL in 2015. So it remains a mystery why this site, if it has ALDARS, does not have more thunderstorms reported. Or why, if ALDARS has been turned off indefinitely, why TSNO doesn’t appear on every observation. Regardless, there are a lot of unreported thunderstorms at this site, including this case; see also cases 763 and 777.
898. Valdosta, Georgia, 22 (23) Jun 2015:
The final case in the June 2015 backlog, comes from Valdosta (KVLD). Between 22/1900-23/0200Z, the reports from KVLD were as such:
METAR KVLD 221853Z VRB03KT 10SM SCT040 36/22 A3006 RMK AO2 SLP185 T03560222
METAR KVLD 221953Z VRB04KT 10SM BKN060 37/22 A3004 RMK AO2 SLP179 T03670217
METAR KVLD 222053Z VRB04KT 7SM RA BKN050 28/23 A3003 RMK AO2 RAB41 SLP173 P0000 60000 T02830228 56019
METAR KVLD 222153Z 19005KT 10SM SCT060 31/24 A3004 RMK AO2 RAE03 SLP178 P0000 T03060239
METAR KVLD 222253Z 15013KT 10SM BKN080 26/19 A3008 RMK AO2 SLP193 T02610189
METAR KVLD 222353Z 17004KT 10SM SCT080 25/21 A3009 RMK AO2 SLP195 60000 T02500206 10372 20244 51022
METAR KVLD 230053Z VRB03KT 10SM -RA BKN100 BKN120 24/23 A3013 RMK AO2 RAB08 SLP209 P0000 T02390228
METAR KVLD 230153Z 01011KT 10SM -RA FEW090 BKN110 24/23 A3013 RMK AO2 SLP210 P0000 T02440233
METAR KVLD 230253Z AUTO 04005KT 10SM -RA FEW090 BKN110 25/23 A3017 RMK AO2 SLP222 P0000 60000 T02500233 51026 TSNO
There were no SPECIs during that period; ASOS was not placed in AUTO/TSNO mode until the 0253Z METAR. That meant LAWRS was logged on
to ASOS until then. According to the NWS AMSS site profile, KVLD is a level C site, whose ALDARS was installed on 25 Aug 2000. It appears ALDARS was enabled, until 0253Z, at which time ASOS was placed in AUTO/TSNO mode.
How then, did all this lightning go unreported?
I used a larger scale map, to show that there were more than 1,000 lightning strikes, that should have been reported as DSNT! Those would be the plots of lightning strikes, between the green 10-mile range ring, and the blue 30-mile range ring around KVLD. 13 lightning strikes hit within the red 5-mile range ring, meeting TS criteria, and many strikes met VCTS criteria. The other end of the scale is revealing as well:
Of the many nearby lightning strikes, one hit the airport! It struck in the woods just west of where runways 13/31 and 4/22 cross. The approximate time of that strike was 2112Z:
The radar at 2110Z, showed level 6 cells, to both the east and south:
It’s a wonder none of the cells were mentioned in any way on the 2253Z METAR. The radar 3 minutes prior to that, showed level 5 rain echoes, 5-10 miles to the SE; with level 3-4 rain echoes closer than that:
By 0050Z, a level 4 cell was about 4-7 miles to the NW:
There’s no doubt there were thunderstorms within 10 miles of KVLD during that period. However, none of that activity was mentioned; either as CB, VCTS, TS, or LTG!
That clears the backlog of cases from June; from before the time I discovered the archive on lightningmaps.org as of case #108 on 23 Jun 2015. I still have some cases from December 2015, which I will now begin to post.
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899. Kendall-Tamiami Executive Airport, Florida, 3 (4) Dec 2015:
Miami Executive Airport (KTMB) is also known as Kendall or Tamiami Airport. Late on December 3rd, so that it extended into the 4th UTC, this was the lightning display around KTMB:
KTMB did record a heavy rainshower during that time:
METAR KTMB 032253Z 04003KT 10SM SCT026 BKN036 OVC060 25/24 A3002 RMK AO2 RAE10B26E37 SLP165 P0000 T02500239
METAR KTMB 032353Z 23015G21KT 2SM +RA BR SCT020 BKN050 OVC090 24/23 A3006 RMK AO2 RAB22 PRESRR SLP179 P0023 60024 T02390233 10283 20239 53023
SPECI KTMB 032357Z 21010G21KT 1 1/2SM +RA BR BKN018 BKN050 OVC075 23/22 A3006 RMK AO2 P0015 T02280217
SPECI KTMB 040011Z 20004KT 3SM RA BR FEW015 BKN026 OVC120 22/21 A3005 RMK AO2 P0038 T02170211
SPECI KTMB 040024Z 16004KT 10SM -RA SCT026 SCT120 22/21 A3004 RMK AO2 P0040 T02170211
METAR KTMB 040053Z 15004KT 10SM -RA FEW120 22/21 A3005 RMK AO2 SLP175 P0043 T02170211
But while .43” of rainfall was recorded; no lightning nor thunder was recorded. The above lightning map had just shown 3 strikes that met TS criteria, and an additional 11 strikes that met VCTS criteria. The nearest bolt struck about 4 miles to the SSW, on SW 176th Street:
Miami Executive Airport had an unreported thunderstorm on 3 Dec 2015.
900. North Perry Airport, Hollywood, Florida, 3 (4) Dec 2015:
Like Tamiami, North Perry Airport in Hollywood (KHWO) also had some lightning issues on 3 Dec:
As noted on the map, none of that lightning was reported by KHWO:
METAR KHWO 031953Z 08006KT 10SM BKN038 OVC050 27/23 A3000 RMK AO2 SLP157 T02720228
METAR KHWO 032053Z 09006KT 10SM -RA FEW022 BKN095 BKN110 26/23 A3001 RMK AO2 RAB39 SLP161 P0000 60000 T02610228 55003
SPECI KHWO 032130Z 02005KT 2SM +RA BR BKN028 BKN048 OVC090 25/23 A3002 RMK AO2 P0020 T02500233
METAR KHWO 032153Z 00000KT 1 1/2SM +RA BR FEW007 BKN016 OVC028 25/24 A3003 RMK AO2 SLP167 P0038 T02500239
SPECI KHWO 032201Z 00000KT 3SM -RA BR FEW007 BKN016 OVC022 25/23 A3003 RMK AO2 P0002 T02500233
SPECI KHWO 032215Z 03004KT 8SM -RA FEW007 BKN014 OVC024 24/23 A3003 RMK AO2 P0005 T02440228
SPECI KHWO 032237Z 01004KT 10SM -RA SCT013 BKN027 OVC100 25/23 A3003 RMK AO2 CIG 020V038 P0006 T02500233
METAR KHWO 032253Z 34005KT 10SM -RA SCT018 SCT032 BKN060 25/23 A3004 RMK AO2 SLP171 P0007 T02500233
METAR KHWO 032353Z 07005KT 10SM -RA SCT046 BKN060 OVC110 24/23 A3004 RMK AO2 RAE29B53 SLP171 P0006 60051 T02440233 10289 20239 51011
SPECI KHWO 040016Z 00000KT 10SM SCT008 BKN047 OVC110 24/23 A3005 RMK AO2 RAE03 P0000 T02440233
METAR KHWO 040053Z 14005KT 7SM RA SCT005 BKN038 OVC047 24/23 A3006 RMK AO2 RAE03B21 SLP179 P0021 T02390233
So the 6-hourly rainfall total of .51”; plus the .21” from the next hour for a total of .73”, meant that there was a clue that the rain was showery, thus falling from convective clouds such as TCU or CB. The IFR visibility of 1.5SM during the heavy rain at 2153Z, was the worst reported hazard during that time. The 18 lightning strikes within 5 miles, didn’t trigger a report for a TS at KHWO. Nor did the 34 strikes between 5-10 miles from the airport, generate a SPECI for a VCTS at KHWO. That’s a total of 52 lightning strikes that should have been reported in some fashion, as either TS or VCTS; that didn’t get reported at all! Not even LTG DSNT was reported for lightning 10-30 miles from the airport- and there was plenty of that, especially to the east. The nearest lightning strike was about ½ mile NE of the airport:
That strike would have been associated with the thunderstorm that hit around 2130Z. The yellow lightning strike plots on the first lightning map, show that there was a second thunderstorm, right before 0100Z, that met VCTS criteria. KHWO had 2 unreported thunderstorms, from mid afternoon to early evening, on Thu 3 Dec 2015.
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Post by hlsto2 on Mar 18, 2016 15:21:32 GMT -5
a number of ltg strikes between 15-20Z within 10 miles of baton rouge...ignored by the obstroller. note TSNO in AUTO mode at 0853 and 0953Z. looks like they had ALDARS turned off. KBTR 181953Z 13005KT 10SM -RA BKN012 BKN060 OVC075 20/18 A2983 RMK AO2 RAB49 SLP099 P0000 T02000178 KBTR 181931Z 10008KT 10SM BKN012 BKN060 OVC075 21/17 A2982 RMK AO2 T02060172 KBTR 181913Z 11011KT 10SM FEW014 BKN060 OVC075 21/17 A2984 RMK AO2 PRESFR T02060172 KBTR 181910Z 11010KT 10SM SCT014 BKN021 OVC075 21/17 A2984 RMK AO2 T02060172 KBTR 181853Z 11009KT 10SM OVC012 21/18 A2986 RMK AO2 RAE1755 SLP109 P0000 T02110178 KBTR 181753Z 10007KT 10SM -RA BKN012 OVC024 21/18 A2987 RMK AO2 RAE1654B39 SLP114 P0000 60000 T02060178 10217 20144 58007 KBTR 181653Z 13006KT 10SM -RA SCT012 BKN027 OVC044 21/17 A2988 RMK AO2 RAB41 SLP119 P0000 T02060172 KBTR 181633Z 10007KT 10SM FEW013 BKN027 OVC037 20/17 A2990 RMK AO2 T02000167 KBTR 181608Z 09008KT 10SM SCT010 BKN042 OVC050 20/16 A2990 RMK AO2 T02000161 KBTR 181553Z 09007KT 10SM OVC009 19/16 A2990 RMK AO2 SLP123 T01940161 KBTR 181453Z VRB06KT 10SM OVC004 17/15 A2989 RMK AO2 SLP121 T01720150 50001 KBTR 181353Z 08005KT 10SM OVC003 16/14 A2991 RMK AO2 SLP126 T01560139 KBTR 181253Z 05008KT 10SM OVC006 15/13 A2990 RMK AO2 SLP123 T01500128 KBTR 181214Z 04005KT 10SM BKN005 BKN028 OVC042 14/13 A2989 RMK AO2 T01440128 KBTR 181205Z 04006KT 10SM FEW007 BKN034 OVC095 14/13 A2989 RMK AO2 T01440128 KBTR 181153Z 03004KT 10SM BKN029 OVC095 14/13 A2989 RMK AO2 SLP120 70022 T01440128 10156 20144 53005 KBTR 181106Z 04003KT 10SM SCT009 OVC095 14/13 A2987 RMK AO2 T01440128 KBTR 181053Z 00000KT 10SM BKN095 14/13 A2987 RMK AO2 SLP113 T01440128 KBTR 180953Z AUTO 05004KT 10SM BKN095 15/13 A2985 RMK AO2 SLP107 T01500128 TSNO KBTR 180853Z AUTO 11003KT 10SM FEW032 SCT055 BKN095 15/13 A2987 RMK AO2 SLP115 T01500128 58015 TSNO  |
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Post by tornado on Mar 21, 2016 12:57:24 GMT -5
901. Ft. Lauderdale Executive Airport, Florida, 3 (4) Dec 2015:
Late afternoon into early evening, on Thu 3 Dec , Ft. Lauderdale Executive Airport (KFXE) had a couple of heavy rain showers:
SPECI KFXE 032125Z 02005KT 2SM +RA BR FEW024 OVC039 22/22 A3001 RMK AO2 P0027 T02220222
METAR KFXE 032153Z 01006KT 2SM +RA BR BKN033 22/22 A3002 RMK AO2 SLP167 P0063 T02220222
SPECI KFXE 032200Z 01006KT 1SM RA BR BKN033 BKN070 OVC100 22/22 A3001 RMK AO2 P0003 T02220222
METAR KFXE 032253Z 33007KT 6SM -RA BR BKN026 OVC055 22/22 A3002 RMK AO2 SLP167 P0023 T02220222
SPECI KFXE 032300Z 35009KT 9SM -RA FEW007 BKN022 OVC050 22/22 A3001 RMK AO2 P0000 T02170217 $
SPECI KFXE 032326Z 01004KT 6SM RA BR FEW026 BKN045 OVC060 22/22 A3002 RMK AO2 P0003 T02170217 $
METAR KFXE 032353Z 00000KT 10SM -RA SCT049 BKN100 OVC120 21/ A3002 RMK AO2 SLP169 P0004 60109 T0211 10261 20211 51008 $
METAR KFXE 040053Z 00000KT 2 1/2SM +RA SCT030 BKN090 21/ A3006 RMK AO2 RAE11B39 SLP182 P0007 T0211 $
SPECI KFXE 040112Z 02004KT 4SM -RA FEW013 BKN041 OVC085 21/ A3005 RMK AO2 P0008 T0211 $
METAR KFXE 040153Z 09008KT 10SM FEW007 21/ A3005 RMK AO2 RAE35 SLP177 P0010 T0211 $
So there had been over an inch of rainfall, as evidenced by the 6-hourly rainfall total of 1.09” at 2353Z. No lightning nor thunder was mentioned in any of those reports, despite this much activity on the lightning plot map:
There were 16 bolts that struck between the 2 range rings, meeting VCTS criteria; as well as 7 bolts that struck within the red 5-mile range ring around KFXE, that met TS criteria. The nearest strikes were about 2 miles to the ESE and SSE:
Somehow, 23 lightning strikes within 10 miles, didn’t result in a thunderstorm getting reported at Ft. Lauderdale Executive Airport. See next case.
902. Pompano Beach Airpark, Florida, 3 (4) Dec 2015:
Just a few miles north of Ft. Lauderdale Executive Airport, is another LAWRS site at Pompano Beach Airpark (KPMP). At the same time KFXE had its unreported thunderstorm, KPMP was reporting this:
METAR KPMP 032153Z 02006KT 4SM RA BR BKN014 BKN029 OVC075 24/24 A3002 RMK AO2 LTG DSNT S AND SW RAB11 SLP166 P0008 T02440244
SPECI KPMP 032203Z 36006KT 2SM +RA BR SCT014 OVC029 24/24 A3002 RMK AO2 LTG DSNT S AND SW P0007 T02440244
SPECI KPMP 032215Z 03008KT 2SM RA BR FEW014 BKN037 OVC070 24/24 A3001 RMK AO2 LTG DSNT S AND SW P0011 T02440244
METAR KPMP 032253Z 35006KT 2SM -RA BR BKN035 BKN043 OVC070 24/24 A3002 RMK AO2 LTG DSNT SE AND S SLP167 P0026 T02390239
SPECI KPMP 032256Z 36008KT 4SM +RA BR BKN027 BKN043 OVC070 24/24 A3002 RMK AO2 LTG DSNT E-S P0008 T02390239
SPECI KPMP 032305Z 35008KT 2 1/2SM +RA BR BKN024 OVC043 24/24 A3002 RMK AO2 LTG DSNT E-S P0017 T02390239
SPECI KPMP 032310Z 36007KT 4SM VCTS +RA BR BKN024 OVC043 24/24 A3002 RMK AO2 LTG DSNT E-S P0022 T02390239
SPECI KPMP 032332Z 35006KT 3SM -RA BR BKN034 OVC050 24/24 A3002 RMK AO2 LTG DSNT E-S P0025 T02390239
METAR KPMP 032353Z 36005KT 3SM -RA BR FEW040 SCT049 24/24 A3003 RMK AO2 LTG DSNT E AND SE SLP169 P0025 60059 T02390239 10267 20239 51012
SPECI KPMP 040043Z 03003KT 7SM -RA BKN011 BKN027 OVC110 24/24 A3005 RMK AO2 LTG DSNT NE AND E AND SW P0001 T02390239
SPECI KPMP 040047Z 05005KT 7SM -RA BKN009 BKN028 OVC100 24/24 A3005 RMK AO2 LTG DSNT ALQDS P0001
METAR KPMP 040053Z 11004KT 7SM -RA SCT007 BKN013 OVC070 24/24 A3006 RMK AO2 LTG DSNT SE AND S SLP179 P0002 T02390239
SPECI KPMP 040112Z 33003KT 4SM +RA BR FEW007 SCT015 OVC019 23/23 A3007 RMK AO2 LTG DSNT E-S P0007 T02330233
SPECI KPMP 040124Z 08004KT 7SM VCTS RA SCT017 BKN027 OVC090 23/23 A3006 RMK AO2 LTG DSNT NE-S P0011 T02330233
SPECI KPMP 040132Z 07008KT 7SM VCTS -RA SCT019 BKN044 BKN090 23/23 A3005 RMK AO2 LTG DSNT NE-S P0012 T02330233
METAR KPMP 040153Z 05003KT 7SM FEW047 23/23 A3005 RMK AO2 LTG DSNT E AND SE RAE45 SLP178 P0012 T02280228
So Pompano Beach did report a thunderstorm in the vicinity (VCTS) from 2310-2332Z. A second VCTS was recorded from 0124-0153Z. The code VCTS is reserved for when lightning is detected between 5-10 miles from the site. But in this case, lightning also struck within 5 miles of the site:
On the map above, the nearest lightning strike is hard to see; it is plotted in orange, right on the orange Interstate 95 Highway, where it crosses Florida route 814. Zooming in shows that plot less than 2 miles to the SW:
That plot, in orange, was after the 3 earlier lightning strikes plotted in purple. 2 separate thunderstorms produced lightning within 5 miles. So in this case, VCTS was reported twice at KPMP; the data shows that at 2 different times TS was warranted.
Comparing lightning strikes from both KFXE and KPMP, show that there were 3-4 lightning strikes that met TS criteria at BOTH sites, that didn’t get reported as such.
903. Opa Locka, Florida, 11 Dec 2015:
An entire week went by, without a lightning case. That is to be expected. It’s also expected that Florida would have much of the December lightning.
In the pre-dawn hours of Fri 11 Dec, ALDARS at Opa Locka (KOPF) recorded VCTS on 2 reports:
METAR KOPF 110853Z AUTO 33003KT 10SM VCTS FEW009 SCT034 BKN070 22/21 A2999 RMK AO2 LTG DSNT NE-S SLP156 T02220206 55000
SPECI KOPF 110918Z AUTO 30003KT 10SM CLR 22/21 A3000 RMK AO2 LTG DSNT NE-S T02170206
SPECI KOPF 110925Z AUTO 03005KT 10SM VCTS FEW060 22/21 A3000 RMK AO2 LTG DSNT E AND S T02170206
SPECI KOPF 110940Z AUTO 07004KT 10SM SCT019 SCT060 22/21 A2999 RMK AO2 T02220206
METAR KOPF 110953Z AUTO 24008KT 10SM FEW019 22/20 A2996 RMK AO2 PRESFR SLP145 T02170200
METAR KOPF 111053Z AUTO 03005KT 10SM CLR 22/19 A3001 RMK AO2 SLP161 T02170194
METAR KOPF 111153Z 34006KT 10SM BKN060 22/18 A3003 RMK AO2 LTG DSNT SE SLP168 T02170183 10228 20217 53012
METAR KOPF 111253Z 34005KT 10SM CLR 22/19 A3005 RMK AO2 LTG DSNT SE AND S SLP176 T02170194
If the above reports were accurate, a lightning map should display lightning plots of 2 different colors, between the 5 and 10 mile range rings. That is what we find:
However, what is also noted on the map above, are 2 lightning strikes within 5 miles. That means TS was justified for 15 minutes, twice during the 4-hour valid time of the map. The blue lightning plot about 2 miles to the NNE, would represent the first strike meeting TS criteria; the orange plot about 3.5 miles to the SE, represented the lightning that met TS criteria for the second time. The blue plot was closer:
The other problem was, the strike to the SE, occurred about 1219Z:
There was no thunderstorm nor thunderstorm vicinity reported that hour. LTG DSNT appeared in remarks, on the METARs before and after 1219Z, meaning that ALDARS detected lightning 10-30 miles from Opa Locka. But because ALDARS either failed to range lightning distances correctly, or possibly even failed to detect some of the lightning; KOPF had 1 report of VCTS when TS was warranted; plus one unreported thunderstorm!
904. Stillwater, Oklahoma, 12-13 Dec 2015:
Stillwater (KSWO) had some lightning issues several hours apart. The first took place between 12/2200-13/0000Z:
 
On those maps, there were 3 lightning strikes that met VCTS criteria; and 2 that met TS criteria. How did LAWRS at KSWO handle that?
METAR KSWO 122153Z 15013KT 10SM FEW080 21/17 A2970 RMK AO2 SLP047 T02110167
METAR KSWO 122253Z AUTO 14012KT 10SM FEW040 SCT055 BKN110 20/17 A2969 RMK AO2 RAB13E44 SLP047 P0001 T02000172 TSNO
METAR KSWO 122353Z AUTO 12010KT 10SM CLR 19/17 A2968 RMK AO2 RAB05E18 SLP042 P0000 60001 T01890172 10217 20189 58005 TSNO
METAR KSWO 130053Z AUTO 13010KT 10SM FEW035 19/17 A2965 RMK AO2 SLP034 T01890167 TSNO
METAR KSWO 130153Z 13015KT 10SM SCT034 BKN044 19/17 A2964 RMK AO2 SLP030 T01890167
LAWRS “handled” the situation, by signing off ASOS; placing it into AUTO/TSNO mode for 3 METARs, and signing back on for the 0153Z METAR. So none of those 5 lightning bolts got reported, as ALDARS cannot detect lightning when it has been disabled by the operator!
On Sun 13 Dec, between 0800-1000Z, the control tower was unmanned, as that period was 2-4 a.m. This time, there was even more lightning around Stillwater:
 
18 lightning strikes met VCTS criteria, while 6 bolts met TS criteria. Remarkably, ASOS was not in AUTO mode at that time:
SPECI KSWO 130800Z 12008KT 10SM BKN017 BKN024 OVC060 18/17 A2952 RMK AO2 RAE0758 P0000 T01780172
SPECI KSWO 130844Z 11010KT 2 1/2SM +RA BR SCT016 BKN033 BKN100 18/17 A2949 RMK AO2 RAE0758B30 P0011 T01780172
METAR KSWO 130853Z 10011KT 1 3/4SM +RA BR SCT014 BKN023 OVC080 18/17 A2949 RMK AO2 RAE0758B30 SLP976 P0023 60023 T01780172 57039
SPECI KSWO 130900Z 09007KT 2 1/2SM -RA BR SCT012 BKN018 OVC029 18/17 A2949 RMK AO2 P0001 T01780172
SPECI KSWO 130905Z 09008KT 5SM RA BR BKN010 BKN020 OVC029 18/17 A2948 RMK AO2 P0004 T01780172
SPECI KSWO 130914Z 09008KT 5SM RA BR BKN008 BKN015 OVC027 18/18 A2947 RMK AO2 P0007 T01780178
SPECI KSWO 130948Z 26005KT 1 3/4SM +RA BR BKN006 OVC012 17/17 A2949 RMK AO2 CIG 003V010 P0020
METAR KSWO 130953Z 2SM RA BR BKN006 OVC012 17/17 A2950 RMK AO2 CIG 003V009 SLP978 P0021 T01720172
SPECI KSWO 130955Z 3SM RA BR SCT006 OVC012 17/17 A2949 RMK AO2 P0000 T01720167
What could account better for the 2 heavy rain showers, than thunderstorms producing them? Since the lightning strike plots were 2 different colors- red and purple- there was lightning striking from storms at 2 different times. The lightning data accounts for the rain in the reports. It’s just that the reports- this time with ALDARS apparently enabled- didn’t account for the lightning. During that 2-hour period, Stillwater had 2 unreported thunderstorms (unless the first storm was still in progress when the second thunderstorm began).
905. Flying Cloud Municipal Airport, nr Minneapolis, Minnesota, 16 Dec 2015:
Flying Cloud Municipal Airport (KFCM) in Eden Prairie (SW of Minneapolis) had a thunderstorm issue during wintry weather on Wed 16 Dec 2015. The reports transmitted from KFCM during that time were as such:
METAR KFCM 161353Z 08011KT 5SM BR OVC008 04/03 A2931 RMK AO2 CIG 005V011 PRESFR SLP934 T00390028
SPECI KFCM 161414Z 09010G17KT 5SM BR BKN012 OVC019 04/03 A2929 RMK AO2 T00390028
SPECI KFCM 161423Z 08010KT 5SM VCTS BR FEW008 BKN012 OVC020 04/03 A2929 RMK AO2 LTG DSNT S T00440028
SPECI KFCM 161437Z 20018G27KT 140V210 1/2SM PL BKN010 OVC015 04/03 A2931 RMK AO2 PK WND 21027/1437 LTG DSNT SE PLB37 CIG 005V011 P0000 T00440028
SPECI KFCM 161440Z 20014G27KT 1/2SM VCTS +RA BR OVC012 03/02 A2931 RMK AO2 PK WND 21027/1437 LTG DSNT SE AND NW RAB39PLB37E40 PRESRR P0003 T00330022
METAR KFCM 161453Z 23006KT 3SM VCTS -RA BR SCT009 OVC015 02/01 A2931 RMK AO2 PK WND 21027/1437 LTG DSNT SE AND NW RAB39PLB37E40 SLP934 P0006 60006 T00220011 56025
So for the hour between 1400-1500Z, Flying Cloud Muni recorded thunderstorms from 5-10 miles from the airport; low ceilings and poor visibility; moderate ice pellets (sleet); heavy rain; and winds gusting to 27 knots. It would have been nice if the thunderstorm data had been accurate:
 
According to the data, while there were 5 lightning strikes that met VCTS criteria; 2 lightning bolts met TS criteria. Both of the nearest bolts struck between 1440-1445Z, and didn’t miss the airport by much! Also, 1440Z was the time when PL changed to +RA, meaning that +TSRA should have been the proper code, once the PL ended. After all, the visibility was still 1/2SM, and wind gusted to 27 knots at 1437Z.
For all the hazards listed above, what other hazards did this line of thunderstorms produce within the airspace of Flying Cloud Muni?
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Post by tornado on Mar 21, 2016 14:31:05 GMT -5
906. Gulfport, Mississippi, 22 Dec 2015:
Between 2000-2300Z on Tue 22 Dec 2015, Gulfport (KGPT) had fog, rain, and gusty winds:
METAR KGPT 221953Z 16010KT 1SM -RA BR OVC002 19/19 A2985 RMK AO2 SLP106 P0001 T01940189 RVRNO
SPECI KGPT 222007Z 15011G16KT 1/2SM -RA FG OVC002 19/18 A2984 RMK AO2 P0001 T01890183 RVRNO
METAR KGPT 222053Z 17009KT 3SM -RA BR BKN003 19/18 A2985 RMK AO2 SLP106 P0003 60004 T01890183 57002
METAR KGPT 222153Z 17011KT 3SM RA BR BKN003 18/18 A2984 RMK AO2 SLP105 P0013 T01830178
SPECI KGPT 222200Z 17010G19KT 2 1/2SM -RA BR BKN003 OVC050 18/18 A2985 RMK AO2 P0001 T01830178
SPECI KGPT 222245Z 17007KT 4SM -RA BR OVC004 18/18 A2983 RMK AO2 P0010 T01830178
METAR KGPT 222253Z 18009G15KT 5SM -RA BR OVC004 18/17 A2984 RMK AO2 SLP105 P0010 T01830172
The ceilings were low IFR the entire period, from 200 to 400 feet. But no thunder nor lightning was mentioned. Lightning data shows that it should have been mentioned:
There were 3 lightning strikes that met VCTS criteria, and 2 that met TS criteria. Pilots already had to deal with low IFR ceilings; and from 2007-2053Z, low IFR visibility. Lightning 3 miles away should have been communicated to pilots as well:
Gulfport had another unreported thunderstorm. That’s the last from this site for 2015- but not the last case from Mississippi…
907. New Iberia, Louisiana, 23 Dec 2015:
In the 40 minutes between 0600-0640Z (0600Z was midnight CST), ALDARS at New Iberia (KARA) recorded a VCTS beginning at 0645Z; and a TS beginning at 0653Z:
METAR KARA 230553Z AUTO 15013KT 10SM OVC006 20/19 A2974 RMK AO2 SLP070 60027 T02000189 10200 20189 402220189 58005
SPECI KARA 230645Z AUTO 11012KT 10SM VCTS SCT007 BKN033 BKN050 19/18 A2971 RMK AO2 LTG DSNT S AND SW PRESFR T01940183
METAR KARA 230653Z AUTO 12013KT 10SM TS SCT007 BKN033 OVC090 19/18 A2970 RMK AO2 LTG DSNT S TSB48 PRESFR SLP057 T01940178
Normally such cases wouldn’t be posted, as they represent lower thresholds met on the FLAWD scale. But prior to 0640Z (which was prior to both the TS and VCTS), notice where the 5 lightning strikes within 10 miles of KARA actually hit:
Bolt #5 struck the airport!
The time of that strike was about 0637Z. That certainly met TS criteria, but TS was not begun for another 16 minutes. Since ALDARS takes a bit of time triggering ASOS to take a SPECI- 6 minutes- the 0637Z bolt couldn’t have been the one ALDARS detected to begin the TS. Using the same time scale for the VCTS, ALDARS taking 6 minutes to trigger ASOS to take a SPECI, takes it to 0643Z. The VCTS began at 0645Z. Is it possible that the bolt that struck runway 16/34 at the airport, was the one that triggered ALDARS to generate the VCTS? If so, ALDARS has a serious flaw! VCTS means the lightning was 5-10 miles away from the ARP (Airport Reference Point), when in this case it was right near the center of runway 16/34! If that bolt was NOT the one that triggered ALDARS to report the VCTS, then ALDARS has a serious flaw! That would mean lightning striking the runway, didn’t get reported at all! Either way, there is a serious issue with ALDARS at KARA- and there have been many other such sites with cases in this lightning project! (see case #909)
908. Dothan, Alabama, 23 Dec 2015:
The third case from 2015 at Dothan (KDHN) came on Wed 23 Dec. Between 1800-2000Z, VCTS was recorded:
METAR KDHN 231753Z 09004KT 9SM VCTS -RA BKN003 OVC023 17/17 A2991 RMK AO2 LTG DSNT ALQDS SLP125 P0004 60172 T01720172 10172 20167 56023
SPECI KDHN 231804Z 09009KT 6SM -RA BR BKN004 OVC023 17/17 A2990 RMK AO2 LTG DSNT ALQDS P0002 T01720167
SPECI KDHN 231834Z 09007KT 6SM +RA BR FEW004 OVC021 17/17 A2989 RMK AO2 LTG DSNT ALQDS P0008 T01720167
SPECI KDHN 231848Z 04008KT 6SM VCTS -RA BR BKN004 OVC021 17/17 A2989 RMK AO2 LTG DSNT NE-S P0013
METAR KDHN 231853Z VRB05KT 6SM VCTS -RA BR SCT004 OVC021 17/17 A2989 RMK AO2 LTG DSNT NE-S SLP119 P0013 T01720167
SPECI KDHN 231901Z VRB06KT 6SM VCTS RA BR BKN004 OVC021 17/17 A2988 RMK AO2 LTG DSNT NE-S P0002 T01720167
SPECI KDHN 231930Z 08008KT 10SM BKN004 OVC021 18/17 A2986 RMK AO2 LTG DSNT NE-SE RAE11 P0002 T01780172
METAR KDHN 231953Z 11009KT 10SM -RA FEW006 OVC019 18/17 A2986 RMK AO2 RAE11B32 SLP107 P0002 T01780172
Were the thunderstorms closer than 5-30 miles away? According to the lightning data, yes:
There were 3 lightning strikes within the red 5-mile range ring around Dothan; those met TS criteria. Since 2 bolts were plotted in red, and 1 in blue; the sequence of reports could have been TS-RA-TS-RA instead of VCTS-RA-VCTS-RA. Or possibly it could have been VCTS-TS-VCTS-RA- VCTS-TS-VCTS-RA. 2 strikes within 2.5 miles were not accounted for:
Dothan reported VCTS, at times when TS was warranted.
909. Spirit Of St. Louis Airport, Missouri, 23 Dec 2015:
Spirit Of St. Louis Airport (KSUS) had a thunderstorm on the morning of Wed 23 Dec:
SPECI KSUS 231146Z 26011KT 1 1/2SM R08R/3000VP6000FT +TSRA BR FEW008 BKN011 OVC019 15/14 A2942 RMK AO2 LTG DSNT ALQDS TSB15RAB10 P0025
METAR KSUS 231154Z 22004KT 1SM R08R/3000VP6000FT +RA BR BKN011 OVC024 15/14 A2943 RMK AO2 TSB15E52RAB10 SLP965 P0034 60034 70034 T01500144 10161 20078 55010
That thunderstorm lasted from 1115Z-1152Z. But that wasn’t the end of the heavy rain:
SPECI KSUS 231203Z VRB06KT 1 3/4SM +RA BR SCT011 BKN031 OVC055 16/14 A2942 RMK AO2 P0007
SPECI KSUS 231210Z 12007KT 2 1/2SM RA BR FEW011 BKN034 OVC085 16/14 A2938 RMK AO2 PRESFR P0010
SPECI KSUS 231217Z 13009KT 8SM -RA FEW011 BKN060 OVC095 16/14 A2939 RMK AO2 P0010
METAR KSUS 231254Z 16010G19KT 10SM -RA FEW055 BKN075 OVC090 16/14 A2936 RMK AO2 SLP942 P0015 T01610144
One clap of thunder, by rule must result in a 15-minute thunderstorm. That’s what happened at 1217Z:
But the thunderstorm was not restarted by KSUS. That was a shame, because that bolt hit just beyond ½ mile from the air traffic control tower:
That bolt struck on airport property, 2,754 feet NE of the control tower. Likely, some airport tenants were affected. So why wasn’t that lightning reported in a second thunderstorm? Did ALDARS not detect it? Or since it was 6:17 a.m., and most of the “weather” on radar had moved to the east, did LAWRS let its guard down?
In dying or weakening thunderstorms, lightning can strike in level 1 or 2 rain echo areas. Or, as we have seen in other cases, it can strike completely outside the area where it is raining. KSUS had an unreported thunderstorm that morning, even though lightning struck the airport!
910. Columbus, Georgia, 23 (24) Dec 2015:
Columbus (KCSG) had a rainy day on Wed 23 Dec, with some thunder reported. But between 24/0200-24/0300Z, the reports from KCSG were as follows:
METAR KCSG 240151Z AUTO 17007KT 10SM -RA BKN010 BKN013 OVC019 18/18 A2990 RMK AO2 SLP120 P0002 T01830178 $
SPECI KCSG 240204Z AUTO 17007KT 10SM -RA BKN009 BKN018 OVC023 18/18 A2990 RMK AO2 P0000 T01830178 $
SPECI KCSG 240214Z AUTO 17009KT 10SM SCT009 SCT014 OVC020 18/18 A2989 RMK AO2 RAE06 P0000 T01830178 $
SPECI KCSG 240222Z AUTO 19008KT 10SM SCT008 BKN014 OVC020 19/18 A2990 RMK AO2 RAE06 P0000 T01890178 $
SPECI KCSG 240233Z AUTO 18012KT 6SM RA BR FEW008 BKN020 OVC060 19/18 A2989 RMK AO2 RAE06B32 P0001 T01890183 $
SPECI KCSG 240248Z AUTO 18010KT 10SM VCTS -RA SCT014 BKN029 BKN043 19/18 A2990 RMK AO2 LTG DSNT SE AND S RAE06B32 P0005 $
METAR KCSG 240251Z AUTO 19009KT 10SM VCTS -RA BKN014 BKN029 BKN060 19/18 A2991 RMK AO2 LTG DSNT SE AND S RAE06B32 SLP124 P0006 60022 T01940183 51006 $
SPECI KCSG 240256Z AUTO 19010KT 10SM VCTS -RA SCT008 BKN015 BKN029 19/19 A2990 RMK AO2 LTG DSNT SE AND S P0000 T01940189 $
SPECI KCSG 240300Z AUTO 18010KT 10SM BKN008 BKN015 BKN029 19/19 A2990 RMK AO2 LTG DSNT SE AND S RAE00 P0000 T01940189 $
So ALDARS instructed ASOS to report VCTS, from 0248-0300Z. That’s the first problem ALDARS had. On page 76 of the 7900.5C, paragraph 10-29 states, in part,
Even a VCTS must have a minimum duration of 15 minutes. The above VCTS at KCSG, lasted for 12 minutes. Besides that, there was more
lightning that struck within 5 miles, than between 5-10 miles away:
 
3 lightning strikes hit along U.S. Highway 27, from 1-4 miles to the NW-N. That should have triggered a SPECI to report TS, but did not. ALDARS at Columbus, Georgia, recorded VCTS at a time when TS was warranted.
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Post by tornado on Mar 22, 2016 10:21:56 GMT -5
911a. Dannelly Field, Montgomery, Alabama, 24 Dec 2015:
The first part of this case, came between 1300-1500Z, which was 7-9 a.m. at Dannelly Field (KMGM):
METAR KMGM 241253Z 25006KT 10SM FEW021 SCT035 BKN050 23/21 A2995 RMK AO2 RAB07E27 SLP141 P0000 T02330211
METAR KMGM 241353Z 00000KT 10SM SCT017 OVC048 23/21 A2996 RMK AO2 SLP143 T02280211
SPECI KMGM 241403Z 00000KT 10SM BKN017 OVC048 23/22 A2996 RMK AO2 T02330217
SPECI KMGM 241437Z 20004KT 10SM OVC013 23/22 A2998 RMK AO2 RAB06E16 P0000 T02330217
METAR KMGM 241453Z 25005KT 8SM -RA SCT014 OVC045 23/22 A2998 RMK AO2 RAB06E16B49 SLP151 P0000 60000 T02330217 53017
SPECI KMGM 241509Z 20005KT 10SM BKN009 OVC047 23/22 A3001 RMK AO2 RAE02 CIG 008V012 PRESRR P0000 T02330217
So no lightning or thunder was mentioned in any of the reports above. Yet, plotted lightning strike data, showed thunderstorm activity N-E-S of KMGM during that time:
41 bolts struck between the 2 range rings, meeting VCTS criteria; 3 bolts struck within the red 5-mile range ring, meeting TS criteria. That rates this as a level 5 case on the FLAWD scale (see part B) alone. The nearest lightning struck 1.5 miles to the SW:
There was an unreported thunderstorm at Dannelly Field that morning. After successfully reporting a thunderstorm a bit later, KMGM had an even more serious unreported thunderstorm…
911b. Dannelly Field, Montgomery, Alabama, 24 (25) Dec 2015:
The second part of this case, came after mid-afternoon on Christmas Eve 2015, when Dannelly Field (KMGM) recorded a thunderstorm:
SPECI KMGM 242102Z COR 000000KT 2SM TSRA BR BKN005 BKN035 OVC042 21/19 A3002 RMK AO2 TSB01 P0005 T02060194
SPECI KMGM 242107Z 35003KT 2SM TSRA BR BKN005 BKN035 OVC042 21/19 A3002 RMK AO2 TSB01 P0005 T02060194
SPECI KMGM 242117Z 36005KT 1 1/4SM TSRA BKN005 BKN009 OVC017 21/19 A3001 RMK AO2 TSB01 P0018 T02060194
SPECI KMGM 242121Z 36005KT 2SM TSRA BKN005 BKN011 OVC017 21/19 A3002 RMK AO2 TSB01 P0019 T02060194
METAR KMGM 242153Z 02004KT 3SM BR OVC006 21/19 A3003 RMK AO2 RAE49 TSB01E49 SLP167 P0019 T02060194
That thunderstorm lasted from 2101-2149Z, or 3:01 to 3:49 p.m. CST. The LAWRS/ALDARS combination appears to have worked at that point. After that point, it did not work at all:
METAR KMGM 242253Z 07006KT 10SM -RA FEW004 BKN040 OVC055 20/19 A3004 RMK AO2 RAB04 SLP169 P0012 T02000189
SPECI KMGM 242310Z 08005KT 10SM FEW005 BKN021 OVC055 20/19 A3005 RMK AO2 RAE03 P0000 T02000189
METAR KMGM 242353Z 09004KT 10SM -RA BKN017 OVC120 20/19 A3008 RMK AO2 RAE03B22 SLP182 P0000 60046 T02000189 10222 20200 53021
METAR KMGM 250053Z 11007KT 3SM +RA BR SCT036 SCT048 BKN095 20/19 A3011 RMK AO2 RAE14B35 SLP194 P0009 T02000189
METAR KMGM 250153Z 15017G22KT 2SM +RA BR BKN043 OVC060 21/19 A3010 RMK AO2 VIS 1 1/2V3 SLP190 P0024 T02060194
METAR KMGM 250253Z 13010G24KT 1 1/2SM +RA BR BKN025 BKN032 OVC044 21/19 A3012 RMK AO2 SLP196 P0047 60080 T02110194 51015
SPECI KMGM 250318Z 11011KT 3/4SM +RA BR FEW008 BKN017 OVC030 21/19 A3014 RMK AO2 P0061 T02060194
SPECI KMGM 250328Z 13014KT 3/4SM +RA BR BKN013 OVC040 21/19 A3012 RMK AO2 P0136 T02060194
SPECI KMGM 250330Z 13015KT 1SM +RA BR BKN017 BKN037 OVC050 21/19 A3012 RMK AO2 P0138 T02110194
METAR KMGM 250353Z 12014G21KT 070V150 1SM +RA BR FEW009 BKN025 OVC050 22/20 A3012 RMK AO2 SLP197 P0175 T02170200
SPECI KMGM 250445Z AUTO 08016G23KT 7SM -RA SCT010 BKN014 OVC019 22/20 A3011 RMK AO2 PK WND 06026/0433 P0119 T02170200 TSNO
The thunderstorm ended at 2149Z; and ASOS was placed into AUTO /TSNO mode by 0445Z. Between those 2 points in time, no reports transmitted by KMGM showed any mention of LTG, TS, VCTS, or even CB. That was a mistake:
As can be seen on the map of lightning strike position plots, set to run from 24/2200Z-25/0200Z; there were a few hundred lightning strikes within 10 miles of Dannelly Field! None of those were reported! In the grid where the airport is located, there were 212 lightning strikes- with all of those hitting within 10 miles! 153 lightning bolts struck within the red 5-mile range ring around KMGM! Perhaps 310 bolts or so, struck within 10 miles. This is how dense the lightning strike coverage was:
Lightning struck the airport, more than once! Yet that still didn’t result in a thunderstorm getting reported at those times. The strike nearest to the air traffic control tower, can be isolated in time to 0306Z:
That was while heavy rain was falling, .61” from the 0253Z METAR to the 0318Z SPECI. On this next map, the control tower appears as a tiny white dot, south of runway 10/28, and west of runway 3/21:
  
The distance from the best-resolved spot of the lightning strike, to the air traffic control tower, was 849 feet:
That position, in the trees just south of Tower Road, is less than 1/6 of a mile from the control tower cab. Yet, no thunderstorm was begun for that lightning bolt!
That was hardly the first near miss the control tower had that evening. At 0104Z, an earlier bolt had also struck, between the control tower, and runway 10/28:
That was the second-nearest lightning strike to the control tower that evening, coming while 3SM +RA was reported. Reports were never updated in a SPECI to show that as +TSRA. At 0115Z, lightning struck the north side of the airport:
That bolt hit north of runway 10/28, close to airports tenants, and general aviation parking. There weren’t any SPECIs taken between 0053Z and 0253Z, despite LTGCG AT AP twice!
Another lightning bolt hit on runway 10/28 at 0353Z:
That was while 1SM +RA was being reported. LTGCG AT AP had also occurred twice during that hour, with no +TSRA being reported; that makes 4 lightning strikes, either at the airport, or within 880 feet (1/6 of a mile) of the control tower!
So to review this case:
• About 350 lightning strikes within 10 miles went unreported
• 156 lightning strikes within 5 miles went unreported
• 3 lightning strikes to the airport went unreported
• 1 lightning strike 849 feet from the control tower, went unreported
• Thunderstorms were within 10 miles of KMGM for a 6-hour period in the evening, but did not get reported (part b of this case)
• A thunderstorm between 7-9 a.m. (part a of this case) also went unreported
• A thunderstorm between the times of parts a and b of this case did get reported, which brings into question how users will know when reports are accurate with regards to thunderstorms
This case ranks as a level 7 on the FLAWD scale.
912. Pascagoula, Mississippi, 24 Dec 2015:
On the morning of 24 Dec, Pascagoula (KPQL) had a couple of heavy rain showers:
METAR KPQL 241053Z AUTO 19009G16KT 4SM -RA BR FEW013 SCT022 OVC049 23/22 A2990 RMK AO2 SLP127 P0009 T02280222 TSNO
SPECI KPQL 241103Z AUTO 20007KT 4SM -RA BR SCT008 BKN033 OVC047 23/22 A2990 RMK AO2 P0000 T02280222 TSNO
SPECI KPQL 241110Z AUTO 20007KT 9SM BKN008 BKN019 OVC049 23/22 A2991 RMK AO2 RAE10 P0000 T02280222 TSNO
METAR KPQL 241153Z AUTO 18006KT 7SM OVC005 22/22 A2992 RMK AO2 RAE10B28E37 SLP134 P0000 60009 70295 T02220222 10233 20222 53016 TSNO
SPECI KPQL 241238Z AUTO VRB06KT 1 3/4SM +RA BR OVC005 22/22 A2993 RMK AO2 RAB1156 P0010 T02220222 TSNO
SPECI KPQL 241249Z AUTO VRB05G15KT 3SM -RA BR OVC005 22/22 A2994 RMK AO2 RAB1156 P0012 TSNO
METAR KPQL 241253Z AUTO 20005KT 4SM -RA BR OVC005 22/22 A2994 RMK AO2 RAB1156 SLP139 P0012 T02220222 TSNO
SPECI KPQL 241303Z AUTO 20007KT 4SM BR OVC004 23/22 A2993 RMK AO2 RAE00 P0000 T02280222 TSNO
SPECI KPQL 241315Z AUTO 17008KT 1 3/4SM +RA BR OVC004 23/22 A2994 RMK AO2 RAE00B07 P0010 T02280222 TSNO
SPECI KPQL 241327Z AUTO 22005KT 3SM -RA BR BKN004 OVC017 23/22 A2994 RMK AO2 RAE00B07 P0017 T02280222 TSNO
SPECI KPQL 241345Z AUTO 19006KT 1 3/4SM BR BKN003 OVC020 22/22 A2995 RMK AO2 RAE00B07E36 P0017 T02220222 TSNO
METAR KPQL 241353Z AUTO 20005KT 1 3/4SM BR OVC002 22/22 A2996 RMK AO2 RAE00B07E36 SLP146 P0017 T02220222 TSNO
Since ALDARS was not left on overnight, a thunderstorm between 6-8 a.m. went undetected:
Of the 8 lightning strikes within 10 miles of KPQL, 2 of those were also within 5 miles. Those were probably produced by the broken line of thunderstorms, passing over southern Mississippi:
KPQL didn’t escape between the breaks for the whole period; at 1238Z and again at 1315Z, 1 3/4SM +RA was recorded. Should either of those have included TS or VCTS? Today, lightningmaps.org added a new feature to its deviation circles: time stamps:
The lightning strike 4 miles to the east of Trent Lott International Airport, hit at 1346Z. Yet ASOS had just ended the rain, in a SPECI 1 minute earlier. The lightning strike 4 miles to the NW of KPQL, hit at 1323Z. ASOS had taken a SPECI for +RA at 1315Z. So for a time, +TSRA could have been recorded- if only ALDARS had been enabled!
913. Macon, Georgia, 24 Dec 2015:
This issue from Macon (KMCN), Georgia, was first noticed by forum user hlsto2:
KMCN 232253Z 12008KT 10SM BKN005 BKN024 OVC044 17/16 A2991 RMK AO2 RAE50 SLP127 P0011 T01670161 KMCN 232246Z 12009KT 10SM -RA BKN005 BKN017 OVC046 17/16 A2991 RMK AO2 P0011 T01670161 KMCN 232238Z 12007KT 10SM -RA SCT005 BKN020 OVC049 17/16 A2992 RMK AO2 P0010 T01670161 KMCN 232228Z 13012KT 10SM -RA SCT004 BKN014 OVC100 17/16 A2992 RMK AO2 P0007 T01670161 KMCN 232153Z 14007KT 10SM -RA BKN004 BKN026 OVC095 17/16 A2991 RMK AO2 SLP128 P0009 T01670161 KMCN 232137Z 14007KT 10SM -RA FEW004 BKN075 OVC110 17/16 A2991 RMK AO2 P0008 T01670161 KMCN 232053Z 13006KT 5SM RA BR SCT060 BKN080 OVC110 17/16 A2990 RMK AO2 SLP123 P0012 60044 T01670161 56015 KMCN 231953Z 14003KT 10SM RA BKN055 OVC070 17/17 A2991 RMK AO2 SLP127 P0010 T01670167 KMCN 231853Z 16004KT 10SM -RA FEW050 SCT070 OVC090 17/17 A2992 RMK AO2 SLP127 P0022 T01720167 KMCN 231753Z 23004KT 10SM RA BKN060 BKN070 OVC090 17/17 A2994 RMK AO2 SLP137 P0016 60141 T01720167 10178 20167 50005 KMCN 231653Z 22004KT 10SM -RA OVC065 18/17 A2995 RMK AO2 SLP140 P0003 T01780172 KMCN 231600Z 22005KT 10SM -RA BKN065 OVC080 18/17 A2996 RMK AO2 P0000 T01780172 KMCN 231553Z 21003KT 1SM -RA BR FEW042 BKN060 OVC075 18/17 A2996 RMK AO2 SLP141 P0012 T01780172 KMCN 231453Z 00000KT 1SM +RA BR FEW022 BKN034 OVC065 18/17 A2993 RMK AO2 RAB06 SLP132 P0038 60110 T01780172 50009 KMCN 231451Z 00000KT 1SM RA BR FEW028 BKN034 OVC065 18/17 A2993 RMK AO2 RAB06 P0037 KMCN 231429Z 30007KT 1SM +RA BR SCT003 BKN025 OVC034 17/17 A2994 RMK AO2 RAB06 P0023 T01720172 KMCN 231408Z 02004KT 1SM -RA BR BKN004 BKN009 OVC016 17/17 A2992 RMK AO2 RAB06 P0000 T01720172 KMCN 231355Z 31003KT 10SM FEW004 BKN012 OVC022 17/17 A2992 RMK AO2 T01720172 KMCN 231353Z 00000KT 5SM BR SCT012 BKN016 OVC022 17/17 A2992 RMK AO2 RAE46 SLP130 P0011 T01720172 KMCN 231253Z 11006KT 3SM -RA BR FEW003 BKN023 OVC045 17/17 A2990 RMK AO2 SLP123 P0061 T01720172 KMCN 231219Z AUTO 30007KT 10SM +RA FEW005 BKN017 OVC024 17/17 A2991 RMK AO2 P0029 T01720167 TSNO a number of strikes between about 4 and 10 miles between 12 and 23Z...no TS reported by the macon ga lawrs. TSNO in AUTO at 1219. looks like they left ALDARS off. 
Between the hour of 2000-2100Z, here was the lightning display around KMCN:
So there were 5 bolts that met VCTS criteria, and 2 strikes that met TS criteria, prior to 2100Z. Did the official reports reflect that?
METAR KMCN 241953Z 13005KT 10SM SCT022 BKN029 OVC035 24/22 A3008 RMK AO2 RAB27E36 SLP181 P0000 T02390217
METAR KMCN 242053Z 33005KT 10SM -RA OVC018 20/19 A3010 RMK AO2 RAB1956 SLP190 P0001 60001 T02000194 53009
SPECI KMCN 242103Z 25005KT 1SM +TSRA BR BKN015 BKN020 OVC026 20/19 A3011 RMK AO2 TSB02 P0007 T02000189
A thunderstorm was begun at KMCN, but not until 2102Z. That was 2 minutes after the valid time of the lightning map. Now that we have time
stamps on the deviation circles, at what time should KMCN have begun a thunderstorm?
The lightning strike due west of the airport, was the closest, at a range of about 4 miles. Its time stamp shows it struck at 2036Z. That was 26 minutes before KMCN began a thunderstorm. The bolt about 5.5 miles to the north, struck at 2022Z. If ALDARS had detected that strike, a VCTS should have been started at that time. Of course, the expected time of a VCTS SPECI would have been 2028Z, since ASOS takes 5 minutes to process the data, and 1 minute to transmit the SPECI.
Because this is a “lead time” issue, this case rates a level 3 on the FLAWD scale. The lead time for "lightning within 5 miles" was -26 minutes.
914. Athens, Georgia, 24 Dec 2015:
24 Dec was a rainy day at Athens (KAHN), with 1.06” of rain that day. It was a steady rain of light to moderate intensity. No heavy rain, lightning or thunder was mentioned in any of the reports. Between 1500-1900Z, here were the reports transmitted from KAHN:
METAR KAHN 241451Z 20007KT 5SM -RA BR FEW055 FEW095 OVC120 21/21 A3008 RMK AO2 RAB08 SLP182 P0003 60003 T02110211 53032
SPECI KAHN 241507Z 19005KT 2 1/2SM -RA BR FEW080 SCT100 OVC120 21/21 A3008 RMK AO2 P0002 T02110206 SPECI KAHN 241514Z 18007KT 3SM -RA BR FEW080 SCT100 OVC120 21/21 A3009 RMK AO2 P0003 T02110206
SPECI KAHN 241523Z 18006KT 2 1/2SM RA BR FEW070 BKN090 OVC110 21/21 A3009 RMK AO2 P0006 T02060206
SPECI KAHN 241539Z 19004KT 3SM -RA BR SCT080 OVC100 21/21 A3010 RMK AO2 P0009 T02060206
SPECI KAHN 241545Z 18003KT 1 3/4SM RA BR FEW060 BKN085 OVC110 21/21 A3011 RMK AO2 P0010
METAR KAHN 241551Z 00000KT 1 1/4SM RA BR FEW048 BKN085 OVC110 21/21 A3010 RMK AO2 SLP188 P0013 T02060206
SPECI KAHN 241601Z 16004KT 2SM -RA BR FEW050 BKN095 OVC110 21/21 A3011 RMK AO2 P0004 T02060206
SPECI KAHN 241616Z 19006KT 1 3/4SM RA BR FEW006 BKN060 OVC110 21/21 A3013 RMK AO2 VIS 1 1/2V3 PRESRR P0007 T02060206
SPECI KAHN 241621Z 17004KT 1 1/4SM RA BR SCT008 BKN023 OVC110 21/21 A3012 RMK AO2 VIS 3/4V2 P0011 T02060206
SPECI KAHN 241628Z 20004KT 1 3/4SM RA BR BKN006 BKN023 OVC100 21/21 A3013 RMK AO2 P0013 T02060206
SPECI KAHN 241637Z 15006KT 2SM RA BR BKN004 BKN008 OVC022 21/21 A3011 RMK AO2 P0015 T02060206
METAR KAHN 241651Z 15006KT 1 1/2SM -RA BR BKN004 BKN043 OVC075 21/21 A3010 RMK AO2 SLP190 P0020 T02060206
SPECI KAHN 241701Z 15008KT 3SM -RA BR BKN004 BKN040 OVC085 21/21 A3008 RMK AO2 PRESFR P0001 T02060206
SPECI KAHN 241705Z 14009G15KT 2 1/2SM -RA BR SCT004 BKN040 OVC100 21/21 A3007 RMK AO2 VIS 2V3 PRESFR P0002 T02060206
SPECI KAHN 241721Z 17006KT 1 3/4SM RA BR BKN004 BKN037 OVC085 21/21 A3011 RMK AO2 P0005 T02060206
SPECI KAHN 241734Z VRB03KT 3SM -RA BR BKN004 OVC033 21/21 A3011 RMK AO2 P0007 T02110211
METAR KAHN 241751Z 16006KT 4SM -RA BR BKN004 OVC100 21/21 A3009 RMK AO2 CIG 003V009 SLP185 P0009 60045 T02060206 10211 20206 50003
METAR KAHN 241851Z 18007KT 2SM RA BR BKN004 BKN021 OVC100 21/21 A3008 RMK AO2 SLP183 P0008 T02060206
SPECI KAHN 241902Z 17008KT 2SM RA BR FEW005 BKN075 OVC100 21/21 A3008 RMK AO2 P0002 T02060206
But also between 1500-1900Z, the lightning display showed this:
 
There were 18 lightning strikes that met VCTS criteria. There were also 3 bolts that struck within the red 5-mile range ring around KAHN, meeting TS criteria. The times of those strikes were 1545Z, 1620Z and 1832Z. That means that while VCTS should have been the predominant weather code; TS ought to have been reported 3 separate times within a 3-hour period.
During a period when there were IFR ceilings and visibilities due to moderate rain (sometimes low IFR conditions), KAHN had 3 unreported thunderstorms (TS), plus unreported thunderstorms-in-the-vicinity (VCTS).
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Post by tornado on Mar 22, 2016 12:31:37 GMT -5
915. Hawkins Field, Jackson, Mississippi, 24 Dec 2015:
Between 2200-2300Z on 24 Dec at Hawkins Field (KHKS), Hawkins Field had a sudden squall to 37 knots, when moderate rain reduced the visibility to .75 miles:
METAR KHKS 242153Z 23006KT 9SM FEW035 27/20 A2991 RMK AO2 SLP122 T02720200
SPECI KHKS 242241Z 16029G37KT 3/4SM RA SQ FEW008 BKN040 OVC060 24/20 A2996 RMK AO2 PK WND 15037/2241 RAB41 PRESRR P0009 T02440200
SPECI KHKS 242249Z 00000KT 1/4SM -RA SCT011 BKN041 OVC060 23/19 A2993 RMK AO2 PK WND 15037/2241 RAB41 P0030
METAR KHKS 242253Z 20004G21KT 1SM -RA SCT017 SCT035 BKN041 22/19 A2994 RMK AO2 PK WND 15037/2241 RAB41 SLP129 P0030 T02220189
Why did that happen? The answer, is that a thunderstorm caused the squally weather:
There were 13 lightning strikes that met VCTS criteria that hour. There were also 8 strikes that met TS criteria. Yet, no thunderstorm was reported. That was despite the nearness of some of the lightning:
 
Notice the time stamp of the bolt plotted in purple, about 6 miles SW of the airport. That bolt struck at 2215Z. If VCTS had been reported for that bolt, pilots and airport workers wouldn’t have been totally surprised by the squall to 37 knots at 2241Z. Also, note that 2 lightning bolts to the SW, met TS criteria at 2235 and 2236Z; while the nearest strike, within a mile to the NNE, hit at 2234Z. The earliest strike that met TS criteria, about 4.5 miles to the S, hit at 2228Z. There ought to have been plenty of warning on the ground, that a thunderstorm was in progress; strong wind gusts can be produced by any thunderstorm. ALDARS, if working properly, would have transmitted a SPECI for the bolt at 2228Z, by 2234Z. But not only was ALDARS not working properly, as it failed to detect any of the lightning; LAWRS did not back up ALDARS when it failed! LAWRS also did not report any of the lightning, nor start a thunderstorm!
So on Christmas Eve, there was an unreported thunderstorm at Hawkins Field, which produced a squall to 37 knots.
916. Hawkins Field, Jackson, Mississippi, 25 Dec 2015:
This is unlike case #911, when I split the case from KMGM into 2 parts; since each issue was within 12 hours of each other. This is the second case in a row from Hawkins Field (KHKS), since this case ended more than 12 hours after the issue comprising case #915.
Between 1000-1600Z on Christmas Day, the reports transmitted by Hawkins Field, were as follows:
METAR KHKS 250953Z AUTO 17009KT 7SM -RA SCT009 BKN020 OVC042 23/22 A3001 RMK AO2 RAB46 SLP152 P0000 T02330222
SPECI KHKS 251015Z AUTO 18010KT 1 3/4SM +RA BR SCT009 BKN019 OVC030 23/22 A3001 RMK AO2 RAE0955B11 P0007 T02330222
SPECI KHKS 251024Z AUTO 18006KT 2SM RA BR SCT009 BKN014 OVC026 23/22 A3001 RMK AO2 VIS 1 1/4V4 RAE0955B11 P0009 T02280222
SPECI KHKS 251030Z AUTO 18005KT 3SM -RA BR FEW007 BKN015 OVC031 23/22 A3000 RMK AO2 RAE0955B11 P0009 T02280222
SPECI KHKS 251035Z AUTO 15007KT 2 1/2SM -RA BR BKN007 BKN015 OVC025 23/22 A2999 RMK AO2 RAE0955B11 P0014 T02280222
SPECI KHKS 251050Z AUTO 21008KT 6SM -RA BR SCT008 BKN011 OVC018 23/22 A3001 RMK AO2 RAE0955B11 P0015
METAR KHKS 251053Z AUTO 21007KT 5SM -RA BR SCT008 BKN011 OVC018 23/22 A3002 RMK AO2 RAE0955B11 SLP156 P0015 T02280222
SPECI KHKS 251100Z AUTO 20007KT 5SM -RA BR BKN008 OVC017 23/22 A3001 RMK AO2 CIG 006V012 P0000 T02280222
SPECI KHKS 251112Z AUTO 17009KT 6SM -RA BR SCT007 BKN018 OVC024 23/22 A3001 RMK AO2 P0000 T02280222
METAR KHKS 251153Z AUTO 18008KT 7SM SCT009 BKN018 OVC036 23/22 A3002 RMK AO2 RAE30 SLP158 P0000 60015 70053 T02280222 10233 20228 51005
SPECI KHKS 251213Z AUTO 18007KT 6SM BR BKN009 BKN017 OVC024 23/22 A3003 RMK AO2 CIG 007V013 T02280222
SPECI KHKS 251230Z AUTO 18008KT 7SM VCTS BKN009 BKN030 OVC065 23/22 A3004 RMK AO2 CIG 007V015 T02280222
SPECI KHKS 251240Z 17008KT 6SM VCTS BR SCT009 BKN025 OVC075 23/22 A3004 RMK AO2 T02280222
METAR KHKS 251253Z 17008KT 6SM -RA BR FEW008 BKN025 OVC075 23/22 A3004 RMK AO2 LTG DSNT N RAB51 SLP163 P0001 T02280217
METAR KHKS 251353Z 17009KT 5SM BR SCT011 BKN022 OVC049 23/22 A3004 RMK AO2 RAE00 SLP166 P0000 T02330222
SPECI KHKS 251403Z 18008KT 5SM BR SCT009 BKN026 OVC032 23/22 A3005 RMK AO2 T02330222
SPECI KHKS 251438Z 17010KT 6SM BR BKN012 BKN020 OVC028 24/23 A3006 RMK AO2 RAB14E24 P0000 T02390228
METAR KHKS 251453Z 17008KT 6SM BR BKN012 BKN019 OVC027 24/22 A3006 RMK AO2 RAB14E24 SLP173 P0000 60001 T02390222 53015
SPECI KHKS 251520Z 17007KT 6SM BR FEW011 BKN025 OVC044 24/22 A3007 RMK AO2 RAB15E16 P0000 T02390222
SPECI KHKS 251531Z 17010G17KT 2SM RA BR BKN013 BKN025 OVC046 23/22 A3008 RMK AO2 RAB15E16B29 P0002 T02330222
SPECI KHKS 251536Z 19009G17KT 1 3/4SM -RA BR SCT013 BKN031 OVC046 23/22 A3008 RMK AO2 VIS 3/4V5 RAB15E16B29 P0003 T02330222
SPECI KHKS 251538Z 20007G17KT 2SM -RA BR SCT011 BKN025 OVC048 23/22 A3008 RMK AO2 VIS 3/4V4 LTG DSNT SW RAB15E16B29 P0003 T02330222
SPECI KHKS 251546Z 19005KT 6SM -RA BR FEW011 BKN023 OVC048 24/23 A3008 RMK AO2 LTG DSNT SW AND W RAB15E16B29 P0003 T02390228
METAR KHKS 251553Z 18008KT 8SM FEW010 BKN023 BKN035 24/23 A3008 RMK AO2 LTG DSNT SW AND W RAB15E16B29E49 SLP178 P0003 T02440228
So ASOS recorded VCTS, from 1230-1253Z. That didn’t match the time of the heaviest rain, which came at 1015Z. Was there any lightning within 5 miles?
Yes, lightning data shows that 12 bolts struck within 5 miles. Zooming in on the data, shows when they hit:
There were 2 separate thunderstorms in that 6-hour time frame. The first storm, produced lightning within 5 miles; at 1032Z, 1034Z, 1039Z, 1042Z, 1043Z, and 1045Z. That was closer to the time of the heavy rain, than when ALDARS recorded VCTS. The second thunderstorm produced lightning within 5 miles at 1524Z and 1529Z. That was followed by ASOS taking a SPECI for the onset of moderate rain, dropping the visibility to 2 miles at 1531Z. But neither the 1032Z thunderstorm, nor the one that began at 1524Z, prompted ALDARS to generate a SPECI for TS. Even the 36 bolts which met VCTS criteria, didn’t match the time when ALDARS did report VCTS:
Again, the VCTS recorded at KHKS, was from 1230-1253Z. Zooming in on the northeast quadrant of the original lightning strike map, near the suburb of Ridgeland, shows several lightning bolts plotted in blue/purple. Most of those bolts struck between 1038Z-1126Z. That raises 2 questions: Why didn’t ALDARS detect that lightning? And, what was ALDARS detecting between 1230-1253Z?
ALDARS at KHKS, missed reporting TS from 1032-1100Z on Christmas Day; then missed reporting VCTS from 1100-1141Z; then later missed reporting another TS from 1524-1544Z. Why is ALDARS still trusted at some sites?
917. Charlotte Amalie, U.S. Virgin Islands, 28 Nov 2015:
The last case in the lightning project, is a backlogged case from the Virgin Islands. It came from Charlotte Amalie (call sign TIST), on the island of St. Thomas, on 28 Nov. Here are some reports from TIST that day:
METAR TIST 281453Z 12010KT 10SM BKN018 BKN028 OVC036 27/24 A2996 RMK AO2 SLP146 60081 T02670244 51008 $
METAR TIST 281511Z 11010KT 10SM FEW020 SCT035 BKN049 27/24 A2997 RMK AO2 T02670244 $
METAR TIST 281553Z 12011KT 10SM -RA FEW018 BKN035 OVC055 26/24 A2995 RMK AO2 RAB23E32B48 SLP141 P0000 T02610239 $
But between 1500-1630Z, there had been some lightning within 10 miles of TIST:
There were actually 2 separate thunderstorms during that 90-minute period. One was to the south, whose lightning met TS criteria:
The first lightning bolt struck the water, about 3.5 miles south of Charlotte Amalie, at 1520Z. A second lightning strike occurred to the SW at 1531Z. As a minimum, a thunderstorm should have been reported by TIST from 1520-1546Z, but was not. The second thunderstorm produced 2 bolts that met VCTS criteria, to the N:
Both of those bolts struck the water about 9 miles north of Charlotte Amalie. The first bolt hit at 1613Z, and the second struck at 1619Z. VCTS ought to have been reported from 1613-1634Z. It doesn’t appear that this site has ALDARS though. If not, VCTS would be irrelevant, and even the storm 9 miles away would be coded as TS. For on page 162 of the 7900.5C, under the comments for Table E-4, it reads:
Charlotte Amalie (TIST) in the U.S. Virgin Islands, had 2 unreported thunderstorms on 28 Nov 2015.
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That ends the data collection phase of the lightning project. Case 917 is the final case posted. I will have further analysis of some of the cases, and of the overall project. If I see any serious lightning issues in 2016, I will post them in one of the QC threads.
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Post by tornado on Mar 23, 2016 11:35:02 GMT -5
I updated case #254 from Peoria, Illinois. The reason being, it had the most LTGCG AT AP; 8 strikes, the times of which I was able to confirm. It turns out the 8th strike to the airport, was closer to the control tower, than in any other case posted. Here's what I added:
Late edit: Since this case had the most lightning strikes at the airport, I revisited it. I was able confirm LTGCG AT AP 8 times:
1. 1341Z 1,397FT
2. 2056Z 4,184FT
3. 2102Z
4. 2103Z
5. 2104Z
6. 2104Z 1,467FT
7. 2104Z
8. 2105Z 413FT
I measured the distances to some of the lightning bolts. It turns out that this case now also has the nearest lightning strike to a control tower, without thunder being reported: 413 feet! That was a bolt that struck at 2105Z:
Despite 6 lightning strikes to the airport in less than 4 minutes, TS was not recorded! The official weather changed from 1SM +RA at 2102Z, to 1/4SM +RA at 2108Z without any mention of 6 lightning strikes to the airport, between those 2 SPECIs! ------------------------ What I didn't have room to post in the original case file, was the raw data I had to sift through:    In just 9 minutes, there were 7 occurrences of LTGCG AT AP! 5 of those were on the middle map above. |
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Post by hlsto2 on Mar 27, 2016 20:37:00 GMT -5
toledo oh lawrs closes up shop early...avoiding the TS...TSNO beginning 2252. they left aldars off? as you can see the ap was peppered by lightning in this graphic from 2315 to 0124Z KTOL 280105Z AUTO 00000KT 4SM -RA BR SCT029 BKN070 OVC090 12/11 A2970 RMK AO2 P0005 T01170111 TSNO KTOL 280057Z AUTO 11005KT 2SM -RA BR SCT023 BKN075 OVC100 12/11 A2971 RMK AO2 P0004 T01170111 TSNO KTOL 280052Z AUTO 07009G16KT 1SM +RA BR SCT023 BKN050 OVC095 12/11 A2968 RMK AO2 SLP055 P0033 T01220111 TSNO RVRNO KTOL 280047Z AUTO 24011G25KT 1 3/4SM +RA BR SCT020 BKN075 OVC095 12/10 A2975 RMK AO2 P0008 TSNO KTOL 272352Z AUTO 09006KT 10SM -RA SCT065 OVC090 14/08 A2972 RMK AO2 RAB38 SLP066 P0001 60001 T01390083 10239 20139 58038 TSNO KTOL 272252Z AUTO 07007KT 10SM SCT065 17/07 A2976 RMK AO2 SLP081 T01670067 TSNO KTOL 272152Z 19010G19KT 10SM CLR 23/07 A2979 RMK AO2 SLP089 T02280072 KTOL 272052Z 19010G21KT 10SM FEW070 23/06 A2983 RMK AO2 SLP102 T02330061 56044 KTOL 271952Z 20012G21KT 10SM CLR 23/06 A2985 RMK AO2 SLP110 T02280056  |
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Post by hlsto2 on Mar 30, 2016 19:03:44 GMT -5
several CG strikes within 5 miles of ap between 21 and 00Z but ft worth spinks lawrs only manages a VCTS. also no entry in present wx for vis of 1 1/4SM at 2245 KFWS 302346Z 19007G12KT 7SM -RA SCT050 SCT070 16/16 A2968 KFWS 302305Z 10010KT 10SM VCTS SCT007 OVC018 16/15 A2964 KFWS 302245Z 29037G48KT 1 1/4SM OVC007 17/14 A2968 KFWS 302153Z 17013G18KT 7SM BKN030 23/19 A2959 KFWS 302053Z 17012G19KT 7SM BKN018 BKN027 24/20 A2963  |
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