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Post by tornado on Jun 20, 2015 16:51:48 GMT -5
104. Bismarck, North Dakota, 19 (20) Jun 2015:
Last night, there were strong thunderstorms moving out of Montana into the Dakotas. The storms
headed for Bismarck ND, and Rapid City SD:
I realized ahead of time, that Bismarck Airport (KBIS) would be impacted (a lot of weather observers,
have forecasting experience and have written TAFs). Upon checking to see what flight activity they had, I found a flight that had just departed. Another flight from DFW was inbound as of 0049Z:
Envoy Air 3306 was to land at Bismarck in 1 hour and 22 minutes. But one could see a LEWP
approaching Bismarck. That stands for Line Echo Wave Pattern, and is indicative of severe
weather. This was the current weather report for Bismarck, that the pilot would have received in the cockpit, for KBIS, valid 3 minutes later:
METAR KBIS 200052Z AUTO 15006KT 10SM CLR 25/18 A2971 RMK
AO2 LTG DSNT W-N SLP055 T02500183
So the first question, is why was ASOS at that site in AUTO mode, with a commercial flight inbound
while severe thunderstorms were approaching? I called the ASOS (701-255-7563), and appended to the end of the weather report was a NOTAM stating, "Bismarck tower hours of operation 6 a.m. local
time to midnight local time." The next question is, why was ASOS in AUTO mode, if the control
tower was open? Isn't that degradation of service?
The tower had those 2 flights to deal with, so they shouldn't have been so busy that they could not
log on to ASOS and augment it. The 0052Z METAR reported clear skies; does this look clear to you?
Envoy Air 3306 should have gotten this lightning information while approaching Bismarck:
Also, the pilot should have had access to the latest convective SIGMET:
CONVECTIVE SIGMET 25C
VALID UNTIL 0455Z
SD ND
FROM 50E MOT-30SSW GFK-40W ABR-30ESE DIK-50E MOT
AREA SEV TS MOV FROM 27030KT. TOPS TO FL450.
HAIL TO 1 IN...WIND GUSTS TO 50KT POSS.
As it turned out, tops were as high as FL600, as a storm about 40 miles east of Rapid City SD,
measured a top of 60,000 feet. Keep in mind that 50KT wind gusts were predicted in that SIGMET.
The TAF predicted this:
TAF KBIS 192320Z 2000/2024 19010KT P6SM VCTS SCT050CB BKN150 FM200100
VRB35G45KT 2SM +TSRA OVC035CB FM200300 34006KT P6SM -TSRA
OVC040CB FM200600 33006KT P6SM SCT012 BKN035 BKN150 FM200900
32005KT 4SM BR BKN012 FM201500 31006KT P6SM SCT035 BKN070
At 0154Z, Envoy Air 3306 was 15 minutes from landing at Bismarck:
After listening to several audio files this week, of controllers talking with pilots; I've noticed that they
identify areas of bad "weather" or "rain". They tend not to mention the word "thunderstorm" unless
they are reading a weather report that contains one. A thunderstorm isn't just an area of heavy rain.
Its downburst winds can precede it by several miles. That's known as the gust front. Looking at the radar
above, perhaps Envoy Air 3306 thought he could land before the heavy rain arrived at Bismarck.
Then this happened:
SPECI KBIS 200148Z AUTO 16014KT 10SM VCTS -RA FEW070 BKN100
OVC110 23/20 A2970 RMK AO2 LTG DSNT ALQDS RAB09
PRESFR P0000
METAR KBIS 200152Z AUTO 15020G25KT 10SM -TSRA OVC100 23/20
A2968 RMK AO2 LTG DSNT ALQDS RAB09 TSB49 PRESFR
SLP044 P0000 T02280200
SPECI KBIS 200202Z AUTO 27040G72KT 230V310 1 3/4SM R31/4500VP6000FT
-TSRA BR SQ FEW012 OVC100 21/19 A2978 RMK AO2
PK WND 25072/0201 LTG DSNT ALQDS PRESRR P0001
T02110189
The light rain arrived at Bismarck. ALDARS or ATC quickly changed the conditions from VCTS -RA to -TSRA. There was lightning just north of the runway at 0152Z. But then a gust to 72 knots occurred! Envoy 3306 had to quickly divert:
Diverting to Rapid City wasn't a piece of cake either; the pilot had to skirt just south of that other line
of thunderstorms passing through South Dakota.
The point is that thunderstorms can produce strong winds out ahead of the cell, ahead of the lightning
and ahead of the heaviest rain. The conditions at 0201Z exceeded the prediction of the SIGMET; that
called for gusts to 50 knots, when a 72-knot gust struck KBIS. The conditions also exceeded that which was called for in the TAF. Identifying hazards as early as possible gives pilots more time to react to adverse weather. Fortunately in this case, the pilot was able to land safely.
A plane on the ground was not as lucky:
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BISMARCK ND
946 AM CDT SAT JUN 20 2015
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0903 PM TSTM WND GST BISMARCK 46.81N 100.78W
06/19/2015 M82 MPH BURLEIGH ND TRAINED SPOTTER
SPOTTER REPORTED A SMALL AIRPLANE FLIPPED OVER ON NORTH
SIDE OF BISMARCK AIRPORT. THIS IS DAMAGE ASSOCIATED WITH
THE MEASURED WIND GUST PREVIOUSLY REPORTED.
This is one of the other resources that can be affected by strong winds. If a Contract Weather Observer had been on duty, ASOS would not have been in AUTO mode. The CWO would have reported something like CB DSNT W-N MOV E, at the time ASOS reported CLR. When CB W MOV E is reported, it's tantamount to saying, "thunderstorm expected at this site soon". It's also likely that a CWO would have begun the TS sooner than 0148Z. That's based on this lightning map, valid 0151Z: 
Here is the same data, with range rings overlaid:
A CWO on duty would have been keeping a close eye on those storms, as Bismarck was under a severe thunderstorm watch. A CWO at KBIS wouldn't have had to wait until the thunderstorm was within 10 miles. They would have begun the thunderstorm from the time they heard thunder. As flat as that part of North Dakota is, they could have easily heard distant rumbles of thunder, from beyond 15 miles (I've heard thunder from 13 miles away in mountainous terrain, and much further than that in flat terrain). There were over 2 dozen lightning bolts that struck in the 10-15 mile range from KBIS (the green range ring is 10 miles). A Contract Weather Observer would have provided even more lead time, by beginning a thunderstorm earlier; and thus providing pilots in the air, and resources on the ground, more time to react to thunderstorms and their associated hazards. That could prove valuable in cases such as these, when winds were much stronger than predicted in either the TAF or convective SIGMET!
105. Norfolk International Airport, Virginia, 20 (21) Jun 2015:
This is a study in contrasts. All day on the 20th, Norfolk Intl (KORF) had ASOS in AUTO mode:
METAR KORF 201151Z AUTO 24006KT 10SM CLR 26/21 A3002 RMK
AO2 SLP166 T02610211 10267 20250 53013 TSNO
METAR KORF 201751Z AUTO 10012KT 10SM BKN049 32/22 A2998 RMK
AO2 SLP151 T03170222 10328 20261 58009 TSNO
METAR KORF 202351Z AUTO 18010G24KT 10SM CLR 30/23 A2987 RMK
AO2 SLP115 T03000233 10328 20300 56017 TSNO
Across the bay, nearby Newport News was signed on to ASOS:
METAR KPHF 201154Z 24009KT 10SM CLR 28/22 A3002 RMK AO2 SLP164
60000 T02830222 10283 20261 53010
METAR KPHF 201754Z 17009KT 140V200 10SM CLR 34/23 A2998 RMK
AO2 SLP151 T03440228 10350 20283 58010
METAR KPHF 202354Z 19012KT 10SM CLR 33/24 A2986 RMK AO2 SLP112
T03330239 10367 20333 56014
By 21/0300Z, Newport News had no flights; while Norfolk Intl had several flights.
Yet, the ASOS at KORF was still in AUTO/TSNO mode:
METAR KORF 210251Z AUTO 18011KT 10SM CLR 28/24 A2986 RMK AO2 SLP112 T02780239 58003 TSNO
METAR KPHF 210254Z 19013G25KT 10SM CLR 31/23 A2984 RMK AO2
LTG DSNT SW-N SLP103 T03060228 58009
ATC at KPHF was signed on to ASOS; ATC at KORF was not signed in. This is the opposite of what you'd expect with flights active at KORF, and not at KPHF. To complicate matters, a line of thunderstorms was bearing down on both airports by 0335Z:
Note both airports had reported clear skies on their last METARs. Satellite data proved otherwise:
Lightning animation showed thunderstorms moving towards both airports:
What drew my attention to this area, was that it was under a severe thunderstorm watch; and that,
in the midst of the line of thunderstorms, there were tops up to 70,000 feet! I regret that I didn't
save the radar summary that showed those tops. I did save a radar animation:
Since ASOS was in AUTO and TSNO modes, one would think there weren't any flights in or out
of Norfolk Intl (KORF) at that late hour. That wasn't the case:
  
  
 
There were some major airlines flying in and out of KORF at that late hour: Delta, American, Southwest. They all had to deal with the fact the KORF had been reporting clear skies; ASOS was in AUTO/TSNO mode; and that a line of thunderstorms was bearing down on the Tidewater area, including KORF. That's bad enough! Then this happened:
Open ticket. The following admin message has been already sent: FAA MAINTENANCE NOTIFICATION .ATLANTA AND SALT LAKE CITY FAA HAVE SCHEDULED MAINTENANCE ON 21 JUNE 15 BETWEEN 0315Z AND 0815Z. . DURING THIS MAINTENANCE WINDOW NO FAA DATA WILL BE
AVAILABLE TO THE NWS FOR DISTRIBUTION TO OUR
CUSTOMERS. THIS INCLUDES ALL FAA METAR REPORTS. . THE REASON FOR THIS MAINTENANCE - RESTORATION OF THE WMSCR/FAA DATABASE.
There was another planned ASOS outage, right at the time the line of thunderstorms was reaching the Norfolk area!
What was the weather during that time?
At 0338Z, lightning was striking near Newport News (KPHF):
At 0357Z, lightning had reached to within 5 miles of Norfolk Intl (KORF):
At nearby Langley Air Force Base , there had been a wind gust to 43 knots at 0350Z:
METAR KLFI 210358Z AUTO 21024G43KT 1/4SM R26/2800FT +TSRA
FG SCT019 BKN036 BKN100 23/21 A2985 RMK AO2 PK
WND 23043/50 VIS 1/4V6 LTG DSNT S-E RAB34 TSB44
SLP115 P0036 T02310210
Norfolk Naval Air Station also reported a wind gust to 43 knots, at 0354Z:
METAR KNGU 210359Z 24021G43KT 2SM TSRA BR FEW020CB SCT090
BKN280 24/22 A2993 RMK AO2 PK WND 24043/0354 PRESRR
SLP134 FREQ LTGICCCCG OHD TS OHD MOV NE TSB44RAB53
SVR T1 SET P0026 T02440222
Fortunately, those military sites weren't affected by the FAA ASOS outage.
At 0409Z, there was LTGCG AT AP at KORF:
0422Z, lightning was still striking close to KORF:
Also at 0434Z:
Archived gridded lightning data showed just how many lightning bolts were striking. The valid time
of the map is 22/0300-0430Z:
59 lightning bolts struck in the same grid as the airport, in that 90 minute period! Note the scale of miles
at the bottom of the map.
There were still flights wanting to land at KORF, but were delayed due to the thunderstorms:
There was a lot of damaging wind last night in Virginia:
So, several arrivals at KORF last night, had to deal with a line of thunderstorms, with incomplete weather data! The last report out of KORF before the outage, was of clear skies with no mention of thunderstorms. That was due to the fact that ATC was not signed in to ASOS; and ASOS was not providing thunderstorm information (TSNO). Our pilots deserve better!
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Post by hlsto2 on Jun 20, 2015 20:42:41 GMT -5
what it boils down to is that the airport was struck by a severe TS...without warning. and we have the evidence that this happens all the time at LAWRS sites. but...wait...ALDARS DID report distant lightning!
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Post by tornado on Jun 21, 2015 22:38:03 GMT -5
106. Owensboro, Kentucky, 21 (22) Jun 2015:
During the hour from 21/2356Z to 22/0056Z, there were 2 SPECIs at Owensboro:
METAR KOWB 212356Z 07006KT 10SM SCT040 31/22 A2998 RMK AO2
56007 T03050222 10327 20300 SLP148
SPECI KOWB 220017Z VRB06KT 10SM SCT044 30/22 A2998 RMK AO2
SPECI KOWB 220019Z 23010KT 10SM SCT044 30/23 A2998 RMK AO2
METAR KOWB 220056Z 15009KT 10SM FEW065 27/24 A2996 RMK AO2
T02720244 RAB24E56 P0000 SLP140
It is unclear why these were taken, as neither met SPECI criteria. In any event, no
lightning or thunder data was mentioned.
But, thunderstorms were headed for Owensboro. First, the 0056Z sky condition of FEW065
ignored taller thunderheads:
To a contract weather observer, that would have been FEW065CB. Both radar and lightning animations showed thunderstorms inbound:
 
Below was the lightning display at 0056Z, the exact time of the METAR:
Owensboro did take a SPECI to begin a thunderstorm 2 minutes later:
SPECI KOWB 220058Z 14010KT 10SM -TSRA FEW065 27/24 A2995
RMK AO2 LTG DSNT N-E TSB58RAB58 P0000 PRESFR
Lightning struck to the northeast at that time, within 5 miles:
The dark thunder sound front from that bolt was still traveling towards KOWB. The time on
that map is 0059Z- which was the time a younger bolt struck to the northwest. But it almost
appears that ATC wasn't satisfied with the 0056Z METAR which didn't show any lightning
or thunder activity, so they quickly cut a SPECI that did.
Later, ATC had to intervene and augment the ASOS:
SPECI KOWB 220113Z 17015G21KT 140V210 1 1/2SM +TSRA FEW002
SCT008 BKN034 26/23 A2998 RMK AO2 FRQ LTGCG ALQDS
TSB0058RAB0058 P0022
There were at least 5 lightning bolts that struck the airport, so ATC couldn't ignore
the thunderstorms by that point. The problem was during the previous hour, there
were at least 25 lightning strikes within the red 5-mile range ring of the chart above;
and many more lightning strikes within the green 10-mile range ring. TS/VCTS
should have been reported well before 0058Z. Here is the gridded lightning archive,
from the period 0000Z-0055Z on June 22nd; which clearly shows lightning within 5 miles
early that hour:
ATC should have known what was coming. A convective SIGMET was out for that area:
CONVECTIVE SIGMET 3E
VALID UNTIL 0255Z
TN KY IN IL
FROM 40N IIU-30NNE PXV-30SSE BWG
LINE SEV TS 40 NM WIDE MOV FROM 29025KT. TOPS ABV FL450.
TORNADOES...HAIL TO 1 IN...WIND GUSTS TO 50KT POSS.
Eventually, a severe thunderstorm warning was issued by the NWS:
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PADUCAH KY
755 PM CDT SUN JUN 21 2015
THE NATIONAL WEATHER SERVICE IN PADUCAH HAS ISSUED A
* SEVERE THUNDERSTORM WARNING FOR...
SOUTHWESTERN SPENCER COUNTY IN SOUTHWESTERN INDIANA...
EASTERN HENDERSON COUNTY IN NORTHWESTERN KENTUCKY...
NORTHWESTERN DAVIESS COUNTY IN NORTHWESTERN KENTUCKY...
* UNTIL 830 PM CDT
* AT 753 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR REED IN
EXTREME NORTHEAST HENDERSON COUNTY...MOVING SOUTH AT 15 MPH.
ANOTHER SEVERE STORM WAS LOCATED JUST WEST OF ROCKPORT IN SPENCER
COUNTY INDIANA.
HAZARD...60 MPH WIND GUSTS AND QUARTER SIZE HAIL.
SOURCE...RADAR INDICATED.
IMPACT...HAIL DAMAGE TO VEHICLES IS EXPECTED. EXPECT WIND DAMAGE
TO ROOFS...SIDING AND TREES.
* LOCATIONS IMPACTED INCLUDE...
OWENSBORO...ROCKPORT...ROBARDS...ST. JOSEPH...STANLEY...EUREKA...
MASONVILLE...HEBBARDSVILLE AND MOSELEYVILLE.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.
&&
LAT...LON 3765 8733 3768 8741 3767 8742 3767 8747
3765 8750 3765 8752 3792 8749 3792 8736
3788 8727 3792 8727 3792 8707 3768 8701
TIME...MOT...LOC 0053Z 338DEG 13KT 3786 8737
HAIL...1.00IN
WIND...60MPH
$$
Owensboro is the county seat of Daviess County.
So ATC must have been trusting in ALDARS to detect the lightning. ALDARS failed. When the lightning
began striking near and then at the airport, ATC had to augment the reports. By 0132Z, 6 lightning bolts
had struck the airport; 2 bolts struck runway 18/36:
The one bolt on the S side of the airport, either struck the Air National Guard building, or very close to it.
Another bolt either struck taxiway D, or very close to it. To the SE, a bolt struck somewhere near taxiway C and the FBO.
Hopefully, airport workers had taken cover indoors by that time.
Personnel could have had even more lead time of lightning within 5 miles, if ALDARS had worked
properly; or, if ATC had turned off ALDARS as unrepresentative, and manually augmented ASOS
for thunderstorm activity. This is what contract weather observers do when it is determined that ALDARS is unrepresentative.
Why is lead time important? It's because this could happen:
That's the 2nd-highest lightning total I've seen in the same grid as the airport when zoomed in (Sugar Land TX had 101 strikes in the same grid).
107. Lansing, Michigan, 22 Jun 2015:
This site had storms moving in from the west:
The above animated lightning map, from Weathertap.com, shows lots of lightning passing through
the Lansing area. Soon, the live lightning data showed bolts striking within 5 miles. The chart below was valid at 1808Z:
At 1812Z, lightning data shows 2 bolts had struck the airport:
At 1828Z, a bolt to the east was detected by 44 stations:
By 1856Z, more lightning was striking to the northeast:
Yet, here were the weather reports coming out of Lansing (KLAN) this past hour and beyond:
METAR KLAN 221753Z 20014KT 10SM SCT037 BKN044 OVC055 26/19
A2993 RMK AO2 SLP129 T02610194 10272 20200 58008
SPECI KLAN 221801Z 21016KT 1 1/4SM R28L/3500VP6000FT +RA
FEW023 BKN035 OVC044 24/21 A2995 RMK AO2 RAB1757
P0003 T02440206
SPECI KLAN 221814Z 22009KT 2SM R28L/4000VP6000FT RA BR BKN035
BKN043 OVC120 22/21 A2991 RMK AO2 RAB1757 P0019
T02220206
SPECI KLAN 221822Z 18004KT 4SM -RA BR SCT033 OVC110 23/21
A2991 RMK AO2 RAB1757 P0020 T02280206
METAR KLAN 221853Z 34016G22KT 3SM R28L/5500VP6000FT RA BR
BKN022 BKN060 OVC110 23/21 A2989 RMK AO2 RAB1757
SLP118 P0021 T02280211
SPECI KLAN 221855Z 35022KT 1 3/4SM R28L/4000VP6000FT +RA
BR BKN022 BKN060 OVC110 23/21 A2989 RMK AO2 P0006
T02280211
SPECI KLAN 221859Z 35019G23KT 3/4SM R28L/2200VP6000FT +RA
BR SCT015 BKN022 OVC060 22/21 A2992 RMK AO2 PK
WND 35026/1857 PRESRR P0018 T02220211
SPECI KLAN 221910Z 25006KT 2SM R28L/2200VP6000FT -RA BR SCT014
BKN022 OVC045 23/22 A2990 RMK AO2 PK WND 35026/1857
VIS 3/4V5 P0035 T02280217
SPECI KLAN 221917Z 28012KT 3SM RA BR SCT018 BKN033 OVC100
22/21 A2991 RMK AO2 PK WND 35026/1857 P0036 T02220211
SPECI KLAN 221922Z 26012KT 1 3/4SM +RA BR SCT013 BKN024 OVC070
22/21 A2991 RMK AO2 PK WND 35026/1857 P0039 T02220211
SPECI KLAN 221929Z 13008KT 1 3/4SM R28L/5000VP6000FT -RA
BR SCT017 BKN040 OVC120 22/21 A2980 RMK AO2 PK
WND 35026/1857 PRESFR P0043 T02220206
SPECI KLAN 221932Z 19008KT 3SM R28L/5000VP6000FT -RA BR SCT017
SCT042 BKN065 22/21 A2981 RMK AO2 PK WND 35026/1857
PRESFR P0043 T02220206
Note that in those reports, which were taken from 1753Z-1932Z, there was no mention of thunder (TS) or lightning (LTG) at all!
So how much lightning did ALDARS miss? The above map is valid for 1932Z, so the oldest bolt would be from 1832Z. I counted 62 lightning bolts within the red 5-mile range ring! That didn't even count the lightning that appeared on the chart valid 1828Z. Somehow, ALDARS missed all that lightning; and ATC didn't augment the METARs nor SPECIs to include any lightning or thunderstorm data- even though 2 bolts struck the airport! Remember, the 4th chart posted, from WeatherTap.com, clearly shows lots of lightning passing over Lansing; as well as the lightningsmaps.org data.
Late edit: here is the archived gridded map that shows the lightning strikes from 1800Z-1930Z on June 22nd near Lansing:
Note the scale on the bottom right of the map. The grids to the north and northeast of KLAN each counted over 100
lightning strikes! The grid where KLAN is located counted 42 lightning strikes! ALDARS counted 0 lightning strikes.
Note: early the next morning, this site recorded a thunderstorm- in remarks:
SPECI KLAN 230439Z 27021G29KT 1SM R28L/4000VP6000FT +RA BR FEW013 OVC019 22/19 A2974 RMK AO2 PK WND 24032/0358 TS OHD MOV E. P0146 T02170194
Within 12 hours of an unreported thunderstorm, this site had a misreported thunderstorm. Because of the amount of lightning that went unreported, plus the 2 bolts that struck the airport, this case is promoted to a level 7 on the FLAWD scale.
108. Burke-Lakefront Airport, Cleveland, Ohio, 23 Jun 2015:
Burke-Lakefront Airport (KBKL) had heavy rain showers at times this morning. Below is a 2-hour block of
weather observations out of KBKL:
METAR KBKL 230753Z 21020G31KT 10SM FEW110 27/22 A2978 RMK
AO2 PK WND 20036/0730 RAB31E40 SLP079 P0000 T02720217
SPECI KBKL 230809Z 30026G38KT 10SM SCT021 BKN032 22/18 A2986
RMK AO2 PK WND 29038/0809 WSHFT 0755 PRESRR T02170183
SPECI KBKL 230819Z 30033G45KT 1 1/2SM +RA BKN021 BKN031 OVC100
22/18 A2985 RMK AO2 PK WND 30045/0815 WSHFT 0755
RAB17 P0019 T02170183
SPECI KBKL 230825Z 29026G44KT 1/2SM +RA FG BKN014 BKN024
OVC038 21/18 A2986 RMK AO2 PK WND 30045/0815 WSHFT
0755 RAB17 P0043 T02060183
SPECI KBKL 230838Z 28017G37KT 1SM RA BR BKN019 BKN031 OVC060
21/19 A2982 RMK AO2 PK WND 30045/0815 WSHFT 0755
RAB17 P0076 T02060189
SPECI KBKL 230844Z 28010KT 3SM +RA BR BKN021 BKN044 OVC060
21/19 A2982 RMK AO2 PK WND 30045/0815 WSHFT 0755
RAB17 P0081 T02060194
METAR KBKL 230853Z 24008KT 10SM -RA SCT021 BKN044 OVC060
21/19 A2981 RMK AO2 PK WND 30045/0815 WSHFT 0755
RAB17 SLP090 P0081 60081 T02110194 53005
SPECI KBKL 230901Z 21009KT 10SM FEW007 BKN038 OVC060 21/20
A2980 RMK AO2 RAE0859 P0000 T02110200
SPECI KBKL 230936Z 20004KT 6SM RA BR BKN017 BKN029 OVC035
21/20 A2982 RMK AO2 RAE0859B28 P0002 T02110200
METAR KBKL 230953Z 23012G17KT 1SM +RA BR SCT013 OVC019 22/19
A2982 RMK AO2 RAE0859B28 SLP094 P0042 T02170194
SPECI KBKL 231005Z 21019G27KT 3SM RA BR SCT019 BKN027 OVC100
22/19 A2979 RMK AO2 PK WND 22027/0957 WSHFT 0950
PRESFR P0015 T02170194
SPECI KBKL 231017Z 23023G29KT 5SM +RA BR BKN040 BKN075 OVC110
22/20 A2981 RMK AO2 PK WND 23029/1015 WSHFT 0950
P0020 T02170200
SPECI KBKL 231020Z 22018G29KT 1 3/4SM +RA BR BKN036 BKN075
OVC095 22/20 A2980 RMK AO2 PK WND 23029/1015 WSHFT
0950 VIS 1/2V5 P0027 T02220200
SPECI KBKL 231029Z 22012KT 3SM -RA BR BKN039 BKN095 BKN110
22/21 A2980 RMK AO2 PK WND 23029/1015 WSHFT 0950
P0028 T02220206
METAR KBKL 231053Z 21010KT 10SM SCT043 23/21 A2981 RMK AO2
PK WND 23029/1015 WSHFT 0950 RAE34 SLP090 P0028
T02280206
At 0815Z, a wind gust of 45 knots occurred. Those are thunderstorm-type winds. Yet, notice for the entire period
of 0753Z-1053Z, there were no references to thunder nor lightning.
That's not what lightning data showed.
First, here is an animated lightning map from Weather Tap:
That shows lightning passing through the third county east of Pennsylvania, on the south side of Lake Erie. That is Cuyahoga
County, where Cleveland is located. So it is easy to see that lots of lightning was observed in Cleveland this morning. The
contract weather observer at KCLE, 12.6 miles to the southwest; reported continuous lightning, as well as lightning to the NE,
which was in the direction of KBKL:
SPECI KCLE 230824Z 33016G30KT 280V350 6SM TSRA FEW022 SCT033
BKN065 23/19 A2987 RMK AO2 PK WND 33030/0820 WSHFT
0810 RAB20 TSB0756 FRQ LTGICCG OHD AND W-N-NE
TS OHD AND W-N-NE MOV SE P0003 T02330194
SPECI KCLE 230920Z 16008KT 10SM TS SCT020 BKN029CB BKN044
BKN130 OVC250 21/19 A2982 RMK AO2 RAB04E13 TSE00B20
CONS LTGICCCCG VC W-N TS VC W-N MOV SE P0000 T02110194
Another view of the lightning data, showed plenty of lightning in the area.
But, this morning I discovered a new feature at lightningmaps.org, which allows one to view detailed archived lightning data.
When I set it to view the time period of 0800-1100Z, this is what the lightning data near Burke-Lakefront showed:
The map above has a grid overlaid. There is a stroke counter for each grid, displayed in the upper left-hand corner of each block. The stroke counter detected 9 bolts of lightning that struck within the same grid as the airport. 14 bolts struck in the grid box to the southwest. The blue dots represent the older strikes, from 0800-0900Z; the red dots would be from about 0900-1000Z. The wind gust to 45 knots occurred at 0815Z. So the lightning data clearly shows there was a thunderstorm at KBKL, lasting about 2 hours. Yet, ALDARS and ATC did not report thunder for those 2 hours!
In case you were wondering what the lightning data looks like with 5 and 10 mile range rings superimposed:
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Post by tornado on Jun 23, 2015 14:36:20 GMT -5
Now that archived, gridded lightning data is available on lightningmaps.org, let's revisit some older cases. This data was originally presented parenthetically between cases 23 and 24.
109. Philadelphia-Northeast Airport, Pennsylvania, 3 Jul 2014:
METAR KPNE 032254Z 21013G21KT 10SM BKN035 OVC047 32/22 A2989
RMK AO2 SLP121 T03170222
SPECI KPNE 032318Z 28033G57KT 2 1/2SM RA SQ FEW012 BKN033 OVC065 29/22 A2991
RMK AO2 PK WND 25057/2317 RAB18 P0000 T02940222
Another severe rain shower? Or was thunder missed at this site? That gust to 57 knots would qualify a thunderstorm as severe, but none was reported. KPNE did not record thunderstorms or lightning at all that day, according to archived METAR data: www.wunderground.com/history/airport/KPNE/2014/7/3/DailyHistory.html?req_city=Philadelphia&req_state=PA&req_statename=&reqdb.zip=19114&reqdb.magic=4&reqdb.wmo=99999
Archived gridded lightning data for that date is now available. It shows this:
Here is the same data, with 5 and 10-mile range rings overlaid:
Notice the valid time of the chart, on the color scale: it is from 03/2300-04/0000Z. The great thing about this feature, is that one can set the time to 5-minute increments. Since the wind gust to 57 knots occurred at 2317Z, I set the time to 2315Z-2320Z. This is what the data showed:
There were indeed lightning strikes during the same 5-minute time frame As the wind gust to 57 knots, within 5 miles of KPNE! That was a severe thunderstorm that went unreported as such!
110. Rome NY, 8 Jul 2014:
METAR KRME 082253Z 32032G50KT 1/2SM RA SQ FEW014 BKN080 OVC100
24/20 A2954 RMK AO2 PK WND 30050/2251 RAB52 SLP999 P0018 T02390200 RVRNO
Here was another “severe rain shower”. Thunder was not reported at this site on the 8th.
4 people were killed in upstate New York, from severe thunderstorms.
From nearby Syracuse, a contract weather site:
SPECI KSYR 082203Z 22026G36KT 1SM R28/2000VP6000FT +TSRA SQ SCT030CB BKN050 OVC075 27/21 A2956 RMK AO2 PK WND 23036/2202 TSB03 PRESRR OCNL LTGCGIC SW TS SW MOV NE P0002
Are we to believe it didn’t thunder yesterday in Rome, New York? According to the METAR archives on Weather Underground, it did not: www.wunderground.com/history/airport/KRME/2014/7/8/DailyHistory.html?req_city=Rome&req_state=NY&req_statename=&reqdb.zip=13440&reqdb.magic=1&reqdb.wmo=99999
Now to archived, gridded lightning data. The following map is valid from 2200-2330Z on 8 Jul 2014:
The airport is right on the line between 2 blocks. To the west, 6 lightning bolts were recorded; to the east, 31 lightning strikes were recorded. To see how far away these lightning bolts were, here is the same data, with range rings overlaid:
All of the strikes on the abovementioned blocks, would fit inside the green 10-mile range ring, which Indicates the distance within which a VCTS ought to be recorded. Many of those were also within the red 5-mile range ring; plus, there were additional strikes to the south that were within 5 miles. Since the 50-knot wind gust occurred at 2251Z, I set the following chart for 2245Z-2255Z:
One of those bolts was 1 mile to the east:
One can clearly see lightning strikes very close to the airport, indicating that a thunderstorm should have been reported. The National Weather Service defines a severe thunderstorm as having large hail, at least 3/4 inches (0.75 inches) in diameter, and/or damaging winds, at least 58 mph, or 50 knots. KRME had a severe thunderstorm that day, but did not report it that way!
111. Fort Smith AR, 23 Jul 2014:
METAR KFSM 231953Z 31035G57KT 5SM -RA SQ FEW034 BKN055 OVC070 27/23 A3001 RMK AO2 PK WND 30057/1949 RAB50 PRESRR SLP156 P0000 T02720228
SPECI KFSM 231956Z 30025G57KT 1 3/4SM RA SQ FEW016 BKN035 OVC065 24/21 A3000 RMK AO2 PK WND 31037/1954 VIS 1/2V5 P0000 T02390211
Despite the fact that there was a wind gust to 57 knots. This goes down “officially” as another "severe rain shower"! The Storm Prediction Center had info on that event on their Storm Reports page. It was listed as:
1949 66 FORT SMITH SEBASTIAN AR 3539 9440 THUNDERSTORM WIND GUSTS TO 66 MPH AT THE FORT SMITH REGIONAL AIPORT.
But it wasn't reported as a thunderstorm in a METAR or SPECI at KFSM! The METAR archives show no thunderstorm report from
KFSM on that date:
www.wunderground.com/history/airport/KFSM/2014/7/23/DailyHistory.html?req_city=Fort+Smith+Regional&req_state=AR&req_statename=Arkansas&reqdb.zip=72903&reqdb.magic=4&reqdb.wmo=99999
The archived lightning data, shows otherwise:
The above map covers the period of 1900Z-2030Z on 23 Jul 2014, centered on KFSM. There were 27 lightning bolts that struck within the same grid as the airport; 137 bolts struck within the grid just to the south! Here is what the same data looks like, with range rings:
One can see that the criteria for reporting TS was met at that time. The exact time of the 57-knot (66 mph) wind gust was 1949Z. Setting the lightning grid to that 5 minute window of 1945Z-1950Z, it can be seen that lightning was striking as close as 1 mile to the west, on the west side of interstate 540:
That wasn’t a severe rain shower that day at Fort Smith, Arkansas, as was reported by the LAWRS site. It was a severe thunderstorm!
112. Texarkana, AR, 23 Jul 2014:
As with Ft. Smith, a mesoscale convective complex with a lot of lightning, moved south along the western Arkansas border. Yet, KTXK was another site that did not report thunder at all on the 23rd:
www.wunderground.com/history/airport/KTXK/2014/7/23/DailyHistory.html?req_city=KTXK&req_state=AR&req_statename=Arkansas&reqdb.zip=71854&reqdb.magic=4&reqdb.wmo=99999
The daily sequence of METARs included another near-severe rain shower:
METAR KTXK 232253Z 01022G45KT 5SM -RA SQ SCT017 BKN034 BKN085 23/20 A3009 RMK AO2 PK WND 01045/2246 RAB46 SLP186 P0002 T02330200
That hour, this was what the archived lightning data showed:
Zooming in to the 10-minute window, which includes the strong wind gust, we find there was indeed lightning
striking close to KTXK:
It is evident that ALDARS/LAWRS failed at Texarkana, as well as Fort Smith, on that date.
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Post by tornado on Jun 24, 2015 10:39:58 GMT -5
113. Allegheny County Airport, Pittsburgh, Pennsylvania, 23 Jun 2015:After 1900Z, a band of moderate rain passed over the Allegheny County Airport (KAGC): METAR KAGC 231853Z 33010G18KT 10SM SCT026 BKN031 BKN046 22/18 A2993 RMK AO2 SLP130 T02220178 SPECI KAGC 231859Z 34010G18KT 1 1/2SM R28/3000VP6000FT -RA FEW015 BKN027 OVC048 21/18 A2992 RMK AO2 RAB58 P0010 T02110183 SPECI KAGC 231907Z 32005KT 1SM R28/3000VP6000FT RA BR SCT025 BKN030 OVC041 21/19 A2992 RMK AO2 RAB1858 P0016 T02110189 SPECI KAGC 231921Z 31005KT 4SM R28/4500VP6000FT -RA BR SCT024 BKN032 OVC080 21/19 A2995 RMK AO2 RAB1858 PRESRR P0024 T02110189 METAR KAGC 231953Z 21004KT 10SM FEW028 SCT060 22/19 A2994 RMK AO2 RAB1858E27 SLP135 P0025 T02220189 What KAGC reported as 1SM RA BR, should have been 1SM TSRA BR.  The time scale on the above chart, is located near the color band; it is valid from 1830Z-2015Z on the 23rd. It shows 81 lightning strikes in the same grid where the airport is located. There were 256 lightning strikes in the grid to the east; 609 strikes in the grid to the south; and 625 lightning strikes in the grid to the SW! But how many of those met VCTS or TS criteria? The next map overlays range rings on the same data:  It is evident that about half of the lightning strikes to the south and southwest, would fall within the green 10-mile range ring. That alone would be about 600 lightning strikes! That would be VCTS criteria, but KAGC did not report VCTS during that time period. There was also over 100 lightning strikes to the NE. Within the red 5-mile range ring, it is evident that there were many lightning bolts which should have triggered ALDARS or the LAWRS observer, to report TS. That was not reported either. Lastly, there were hundreds of bolts that struck outside the green 10-mile range ring, but within 30 miles; that should have prompted at least a DSNT LTG remark. That also was not reported. KAGC completely missed what appears to be 2 separate thunderstorms! One passed to the north, and one to the south. 114. Clarksburg, West Virginia, 23 Jun 2015:The airport at Clarksburg (KCKB) had a band of moderate rain move through after 1900Z: METAR KCKB 231853Z 28007KT 8SM BKN034 BKN050 BKN065 29/23 A2993 RMK AO2 SLP119 T02940228 SPECI KCKB 231912Z 25013G21KT 1 3/4SM RA SCT030 BKN037 OVC070 27/23 A2993 RMK AO2 RAB07 P0002 T02670233 SPECI KCKB 231921Z 23007KT 3SM -RA FEW029 SCT035 BKN044 28/24 A2993 RMK AO2 RAB07 P0005 T02830244 METAR KCKB 231953Z VRB06G14KT 9SM SCT038 29/24 A2993 RMK AO2 RAB07E24 SLP118 P0009 T02940244 According to lightning data, the report of 1 3/4SM RA should have been 1 3/4SM TSRA.  The above map is valid from 1900-2000Z, the hour when the heaviest rain passed over Clarksburg. There were 5 lightning bolts that struck within the same grid as KCKB Airport; while 54 bolts struck in the grid to the east. To see how many of those were within 5 miles, here is a map of the same data, within rang rings overlaid:  All 5 of the bolts from the same grid as KCKB, plus 3 bolts to the east, were within the red 5-mile range ring. That should have triggered a TS report at KCKB during that hour, but no TS was reported. Many more bolts struck within the green 10-mile range ring; yet, VCTS was not reported at KCKB that hour. Not even a remark for DSNT LTG was recorded. Clarksburg simply missed a thunderstorm that hour; whether this is attributed to ALDARS or LAWRS depends on whether ALDARS is installed at that site. 115. Philadelphia-Northeast Airport, Pennsylvania, 23 Jun 2015:Here are some reports from Philadelphia Northeast Airport (KPNE) yesterday: METAR KPNE 232154Z AUTO 24014G20KT 10SM CLR 33/20 A2977 RMK AO2 SLP078 T03280200 TSNO SPECI KPNE 232221Z AUTO 27020G48KT 1 3/4SM +RA BKN050 BKN070 BKN085 24/17 A2984 RMK AO2 PK WND 30048/2212 RAB12 PRESRR P0005 T02440172 TSNO SPECI KPNE 232225Z AUTO 27017G29KT 3SM RA FEW030 BKN070 OVC085 24/18 A2983 RMK AO2 PK WND 30048/2212 RAB12 P0006 T02390178 TSNO METAR KPNE 232254Z AUTO 24008KT 10SM -RA 23/19 A2980 RMK AO2 PK WND 30048/2212 RAB12 SLP090 P0008 T02330189 TSNO $ KPNE was in AUTO mode from 2154Z-2254Z. Which is odd, because the previous Tuesday, the 16th; they were not: METAR KPNE 162154Z 30011G17KT 10SM FEW047 BKN080 OVC120 31/19 A2985 RMK AO2 SLP106 T03060194 METAR KPNE 162254Z 27014G21KT 10SM FEW044 FEW050 29/19 A2987 RMK AO2 SLP113 T02940189 So KPNE was signed off ASOS, which was then in AUTO/TSNO mode, when severe weather struck the larger Philadelphia Airport: SPECI KPHL 232200Z 30045G60KT 3/4SM R09R/1800VP6000FT +TSRA SQ SCT049CB SCT065 BKN085 OVC200 32/21 A2988 RMK AO2 PK WND 31060/2159 RAB2159 PRESRR CONS LTGICCG OHD TS OHD MOV SE P0000 T03170211 $ The strongest winds recorded at KPNE, were 48 knots. So was that a "near severe rain shower"? No. Lightning data shows it was a near-severe thunderstorm. The first map is zoomed in on the airport, and is valid from 2200Z-2300Z on 23 Jun 2015:  One can easily count 4 lightning bolts that struck the airport. LTGCG AT AP should have been reported early in the 2200Z hour; according to the color scale, the purple and blue dots represent lightning strikes that occurred within the first 20 minutes of the hour. Keep in mind that the time of the 48-knot wind gust at KPNE, was 2212Z. That's about the same time the LTGCG AT AP was occurring (but was not reported). The next map, also valid for the same hour, shows the bigger picture:  There were hundreds of lightning bolts striking near KPNE, especially to the south! The same grid where KPNE is located, recorded 109 lightning strikes; 213 struck the grid to the west; 475 bolts struck the grid to the south; 312 bolts struck the grid to the SW; 392 struck the grid to the SE. Yet, ATC was not signed on to ASOS, and was in AUTO and TSNO modes. Philadelphia-Northeast is a level C site, but was providing level D service at that time. Remember, they were signed on to ASOS the previous Tuesday evening. Why was ASOS in AUTO mode this Tuesday evening? Contract weather site Philadelphia International Airport, gave 9 minutes of lead time before the storm struck there: SPECI KPHL 232150Z 21009KT 10SM TS SCT045CB BKN085 BKN200 OVC250 34/22 A2976 RMK AO2 TSB50 CONS LTGCG VC SW-VC N TS VC SW-VC N MOV SE $ METAR KPHL 232154Z 23009KT 10SM TS SCT055CB BKN085 BKN200 OVC250 33/22 A2977 RMK AO2 TSB50 SLP081 CONS LTGCG VC SW-VC N TS VC SW-VC N MOV SE T03330222 $ SPECI KPHL 232200Z 30045G60KT 3/4SM R09R/1800VP6000FT +TSRA SQ SCT049CB SCT065 BKN085 OVC200 32/21 A2988 RMK AO2 PK WND 31060/2159 RAB2159 PRESRR CONS LTGICCG OHD TS OHD MOV SE P0000 T03170211 $ By reporting TS, CB in the body of the report, and CONS LTG at 2150Z, users knew a strong thunderstorm was within 10 miles. Continuous lightning is a sign that the storm is strong. The observer also reported TS VC SW-VC N MOV SE. SW-N includes NW, so in essence the storm was reported as moving straight towards the point of observation- the airport. Indeed that verified. What a contrast to how things were reported at KPNE! The following is the previous map, to include range rings:  From the number of lightning bolts located within the red 5-mile range ring, it is clear that KPNE should have reported a thunderstorm. It did not, because it was logged off ASOS. Is that because ATC cannot handle near-severe thunderstorms? If so, why would we want to replace contract weather observers with air traffic controllers, at our nation's largest airports? 116. Atlantic City, New Jersey, 23 Jun 2015:The entire northeastern corridor knew that severe weather was possible late Tuesday. It seems KACY signed off ASOS to let it handle the severe weather: METAR KACY 231554Z 21011KT 10SM CLR 32/23 A2991 RMK AO2 SLP126 T03220233 METAR KACY 231654Z AUTO 21009KT 10SM CLR 33/23 A2989 RMK AO2 SLP119 T03330228 TSNO METAR KACY 240254Z AUTO 29007KT 10SM CLR 22/20 A2990 RMK AO2 RAE18 PRESRR SLP124 P0000 60019 T02170200 53009 TSNO METAR KACY 240354Z 22006KT 10SM CLR 22/21 A2990 RMK AO2 SLP124 T02170206 Atlantic City, a level D site, signed off ASOS for the 1654Z METAR. That's 12:54 p.m. local time, an odd time to sign off. They signed back on to ASOS by 0354Z, which was 11:54 p.m. local time. Again, it's common for sites to be in AUTO mode overnight; but yesterday, KACY was in AUTO mode from about noon to midnight. In the meantime, this happened: METAR KACY 232154Z AUTO 22015G19KT 10SM CLR 34/22 A2979 RMK AO2 SLP085 T03390222 TSNO SPECI KACY 232244Z AUTO 32038G49KT 9SM SQ FEW060 SCT090 28/19 A2990 RMK AO2 PK WND 30049/2244 WSHFT 2230 PRESRR T02830194 TSNO SPECI KACY 232251Z AUTO 32024G49KT 1 3/4SM +RA BR SCT037 BKN060 BKN090 22/19 A2992 RMK AO2 PK WND 30049/2244 WSHFT 2230 RAB45 PRESRR P0000 TSNO METAR KACY 232254Z AUTO 32015G49KT 1 1/4SM +RA BR BKN035 BKN055 BKN090 22/19 A2990 RMK AO2 PK WND 30049/2244 WSHFT 2230 RAB45 SLP124 P0004 T02170194 TSNO ASOS was in AUTO/TSNO mode, when a 49-knot gust occurred. That would go down as another "near severe rain shower". But lightning data proves it was a near-severe thunderstorm.  On the above map, one can see a yellow dot just west of the Garden State Parkway, 2 grids to the south of the airport. The valid time of the map is 2200Z-2300Z Tue 23 Jun 2015. Below is the bigger picture, valid at the same time:  The yellow dots to the NNW-NE, represent newer lightning strikes that hour, which would have been about 2240-2300Z. The peak wind that hour was at 2244Z, and was a gust to 49 knots. KACY had no chance to record a near-severe thunderstorm as long as ASOS was in AUTO/TSNO mode; which it was for that hour. The data shows that at 2244Z, TS SQ should have been reported. Here is the same data with range rings:  Since there were many lightning strikes within the green 10-mile range ring, VCTS should have been reported. The 1 bolt that struck to the south was very close to 5 miles, so it is depends on where the airport reference point is, whether that bolt warranted a TS. If not, that brings up an important point. VCTS can produce strong wind gusts! If a CWO had been on duty in the above situation, TS SQ would have been reported (since a CWO would not report VCTS). Since there was LTGCG W-N that was occurring around H+30 (according to the orange-colored dots and the color scale), a CWO would have already been reporting a thunderstorm, before the gust to 49 knots occurred. As it was, the reported weather went from 22015G19KT 10SM CLR to 32038G49KT 9SM SQ FEW060 SCT090 .
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Post by tornado on Jun 24, 2015 14:16:14 GMT -5
117. Sikorsky Memorial Airport, Bridgeport, Connecticut, 23 Jun 2015:At Sikorsky Memorial Airport (KBDR), these were the reports from 2000Z-2100Z on the evening of Tue 23 Jun 2015: METAR KBDR 231952Z 21009KT 10SM FEW046 28/22 A2976 RMK AO2 PRESFR SLP077 T02830217 SPECI KBDR 232008Z 24021G31KT 1 1/4SM RA FEW031 SCT047 BKN070 27/22 A2978 RMK AO2 PK WND 20031/2004 RAB06 P0000 T02720222 SPECI KBDR 232015Z 24008G26KT 3/4SM -RA SCT022 SCT048 BKN070 27/23 A2976 RMK AO2 PK WND 20031/2004 RAB06 P0015 T02670228 SPECI KBDR 232019Z 21010KT 2 1/2SM -RA FEW022 SCT055 BKN070 27/23 A2975 RMK AO2 PK WND 20031/2004 VIS 1 R29 SE RAB06 P0015 T02720233 SPECI KBDR 232026Z 20011KT 8SM -RA FEW031 SCT055 BKN070 28/23 A2974 RMK AO2 PK WND 20031/2004 RAB06 PRESFR P0015 T02780228 METAR KBDR 232052Z 26005KT 9SM FEW039 SCT095 28/23 A2975 RMK AO2 PK WND 20031/2004 RAB06E38 SLP073 P0015 60015 T02780228 58006 Rain dropped the visibility to 3/4SM, making the airfield low IFR at 2015Z. But was there more happening at that time? Yes. Here is a closer view of that hour's lightning data near Bridgeport:  Lightning was striking close to the airport. But was there a thunderstorm within 5 miles? Here is a larger view of the same hour:  How much lightning was within the red 5-mile range ring on the following chart?  Certainly, enough lightning was striking within 5 miles, to record a thunderstorm. But ALDARS/ATC missed that at KBDR last night. There was also enough lightning to report a VCTS; which, if reported, may have given the airport more lead time. 118. Gulfport-Biloxi Regional Airport, Mississippi, 23 Jun 2015:During the period of 1900Z-2000Z, Gulfport-Biloxi Regional (KGPT) had some rough weather: METAR KGPT 231853Z 30013G24KT 260V330 1/2SM +RA BKN026 BKN055 OVC085 27/18 A3013 RMK AO2 RAB04 SLP201 P0061 T02670183 RVRNO SPECI KGPT 231900Z 32012G41KT 1/4SM +RA BKN016 BKN070 OVC085 26/20 A3018 RMK AO2 PK WND 01041/1858 PRESRR P0064 T02560200 RVRNO SPECI KGPT 231914Z 26024G58KT 1/4SM +RA SQ VV014 26/19 A3010 RMK AO2 PK WND 26058/1911 P0132 T02610189 RVRNO SPECI KGPT 231921Z 32018G42KT 290V350 1/2SM RA BKN014 OVC070 24/19 A3011 RMK AO2 PK WND 26058/1911 WSHFT 1905 P0140 T02440189 RVRNO SPECI KGPT 231924Z 36017G23KT 1SM +RA BKN016 BKN070 OVC090 25/21 A3011 RMK AO2 PK WND 26058/1911 WSHFT 1905 VIS 1/4V3 P0141 T02500206 RVRNO SPECI KGPT 231929Z 36013G23KT 2SM RA SCT018 BKN070 OVC090 27/21 A3010 RMK AO2 PK WND 26058/1911 WSHFT 1913 P0142 T02720211 SPECI KGPT 231937Z 36009KT 8SM -RA SCT029 BKN070 OVC090 27/21 A3010 RMK AO2 PK WND 26058/1911 WSHFT 1913 P0142 T02670206 METAR KGPT 231953Z 36005G15KT 10SM -RA FEW045 SCT070 BKN090 27/21 A3011 RMK AO2 PK WND 26058/1911 WSHFT 1913 SLP194 P0142 T02670211 There was a wind gust to 58 knots at 1911Z. That was officially a severe rain shower, as no thunder nor lightning was reported. But was that really the case? Between 1900Z and 1930Z, the lightning map below shows that 4 bolts struck close to KGPT:  Actually, at least one bolt struck on airport property. That was LTGCG AT AP, but was not even reported. Here is a larger view for the same time period:  There were 14 lightning bolts in the same grid as KGPT during that half hour. Here is what the same data looks like, with range rings added:  16 lightning bolts can be counted as having struck within the red 5-mile range ring, between 1900Z-1930Z. That should have triggered ALDARS/LAWRS to begin a thunderstorm. It did not. Therefore, KGPT missed
reporting a severe thunderstorm on the evening of Tue 23 Jun 2015.119. Norfolk, Virginia, 24 Jun 2015:Norfolk International Airport (KORF) again had its ASOS in AUTO/TSNO, with a line of thunderstorms bearing down on it: METAR KORF 240551Z AUTO 03011KT 6SM -RA FEW009 BKN030 OVC037 24/22 A2998 SPECI KORF 240558Z AUTO 03011G22KT 3SM +RA BR FEW009 BKN024 OVC047 24/22 A3000 RMK AO2 P0004 T02390217 TSNO SPECI KORF 240610Z AUTO 02014G19KT 6SM -RA BR BKN009 BKN019 OVC049 24/22 A2999 RMK AO2 P0004 T02390217 TSNO SPECI KORF 240621Z AUTO 35011G22KT 1 3/4SM +RA BR BKN007 BKN016 OVC049 23/22 A3002 RMK AO2 P0013 T02330217 TSNO SPECI KORF 240634Z AUTO VRB05G20KT 3/4SM R05/2600V5000FT +RA BR FEW005 OVC011 23/22 A3003 RMK AO2 PRESRR P0071 T02280217 TSNO SPECI KORF 240649Z AUTO 25010G18KT 2SM R05/1200VP6000FT +RA BR FEW005 OVC022 23/21 A3000 RMK AO2 P0127 TSNO METAR KORF 240650Z AUTO 25007G18KT 2SM R05/1200VP6000FT +RA BR FEW007 BKN024 OVC070 23/21 A3000 SPECI KORF 240656Z AUTO 24006KT 3SM R05/6000VP6000FT +RA BR FEW009 BKN030 OVC070 22/21 A2998 RMK AO2 PRESFR P0006 T02220211 TSNO SPECI KORF 240724Z AUTO 20008KT 10SM -RA FEW070 SCT080 BKN120 23/21 A2997 RMK AO2 WSHFT 0704 P0013 T02280206 TSNO There was clearly lightning very close to KORF:  The above map is valid from 0600Z-0730Z on the 24th. So is the map below, which shows a bigger view:  There were hundreds of lightning strikes near KORF! But how many were within 5 miles? Here is the same data, with range rings:  Clearly, TS and VCTS should have been reported at that time. But ASOS was in AUTO/TSNO mode. Airnav.com lists the KORF ATCT as continuous attendance. So why is this level C site, providing
level D service so much of the time?
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Post by tornado on Jun 24, 2015 16:04:43 GMT -5
what it boils down to is that the airport was struck by a severe TS...without warning. and we have the evidence that this happens all the time at LAWRS sites... Well, there were 7 LAWRS sites on June 23rd alone, that didn't report thunderstorms, when they should have. |
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Post by tornado on Jun 25, 2015 12:29:10 GMT -5
120. Gulfport-Biloxi Regional Airport, Mississippi, 24 Jun 2015:On the evening of June 24th, Gulfport-Biloxi Airport (KGPT) reported heavy rain showers, from thunderstorms in the vicinity: METAR KGPT 242053Z 20005KT 10SM FEW110 31/24 A3009 RMK AO2 LTG DSNT NW-NE SLP189 T03060244 56009 SPECI KGPT 242106Z 33020G26KT 10SM VCTS FEW026 SCT033 BKN090 29/23 A3010 RMK AO2 PK WND 33026/2106 LTG DSNT NW-NE T02890228 SPECI KGPT 242123Z 31011G19KT 10SM VCTS -RA FEW030 BKN050 OVC090 25/21 A3011 RMK AO2 PK WND 33027/2108 WSHFT 2103 LTG DSNT W-NE RAB22 P0000 T02500206 SPECI KGPT 242130Z 31014KT 1 1/4SM VCTS RA BR FEW011 SCT029 OVC050 23/21 A3012 RMK AO2 PK WND 33027/2108 WSHFT 2103 LTG DSNT W-NE RAB22 P0007 T02330211 SPECI KGPT 242134Z 29014G21KT 3/4SM VCTS +RA BR FEW009 BKN037 OVC050 23/21 A3013 RMK AO2 PK WND 33027/2108 WSHFT 2103 LTG DSNT W-NE RAB22 PRESRR P0017 T02280211 RVRNO SPECI KGPT 242144Z 33005G20KT 1/4SM VCTS +RA FG FEW010 BKN018 OVC050 22/21 A3013 RMK AO2 PK WND 33027/2108 WSHFT 2103 LTG DSNT ALQDS RAB22 P0052 T02220211 RVRNO METAR KGPT 242153Z 32008KT 280V340 1/4SM VCTS +RA FG FEW011 OVC016 23/21 A3013 RMK AO2 PK WND 33027/2108 WSHFT 2103 LTG DSNT ALQDS RAB22 SLP203 P0087 T02280211 RVRNO SPECI KGPT 242159Z 31008KT 1/2SM +RA FG BKN024 OVC070 22/21 A3013 RMK AO2 LTG DSNT ALQDS P0005 T02220211 RVRNO SPECI KGPT 242214Z 30004KT 5SM VCTS +RA BR BKN031 OVC070 23/22 A3012 RMK AO2 LTG DSNT ALQDS P0017 T02280217 METAR KGPT 242253Z 20003KT 6SM -RA BR BKN110 23/22 A3008 RMK AO2 LTG DSNT NE AND E AND W SLP185 P0022 T02280217 The current FAA regulation for reporting thunderstorms in the vicinity (VCTS) is FAA Order 7900.5C, which states,
But within 5 nautical miles of the airport, there was a lightning strike near KGPT that went unreported:
Here is the same data, valid 2100-2230Z on Wed 24 Jun 2015, with range rings added:
So ALDARS missed one bolt close to the airport. How close?
That bolt struck 4,798 feet from the terminal; to the north just off Creosote Road. That is less than 1 mile.
We can even determine the 5-minute window when it struck:
The chart above is valid 24/2135Z-2140Z. That closely matches the time the airfield dropped to low IFR conditions,
supposedly from a VCTS:
SPECI KGPT 242134Z 29014G21KT 3/4SM VCTS +RA BR FEW009 BKN037
OVC050 23/21 A3013 RMK AO2 PK WND 33027/2108 WSHFT
2103 LTG DSNT W-NE RAB22 PRESRR P0017 T02280211
RVRNO
SPECI KGPT 242144Z 33005G20KT 1/4SM VCTS +RA FG FEW010 BKN018
OVC050 22/21 A3013 RMK AO2 PK WND 33027/2108 WSHFT
2103 LTG DSNT ALQDS RAB22 P0052 T02220211 RVRNO
The report at 2144Z, should have read 1/4SM +TSRA
121. Hawkins Field, Jackson, Mississippi, 24 Jun 2015:
On the evening of Wed 24 Jun 2015, Hawkins Field (KHKS) recorded a 1-hour period that included
heavy rains:
METAR KHKS 242053Z 00000KT 6SM -RA BR FEW038 SCT075 BKN095
28/26 A3008 RMK AO2 RAB1959 SLP176 P0027 60027
T02780261 58019
SPECI KHKS 242121Z 16016G26KT 10SM BKN038 BKN046 OVC075 25/22
A3011 RMK AO2 PK WND 16030/2104 WSHFT 2101 RAE04
P0000 T02500217
SPECI KHKS 242135Z 17018G23KT 9SM -RA FEW020 BKN038 OVC047
25/22 A3017 RMK AO2 PK WND 16030/2104 WSHFT 2115
RAE04B29 PRESRR P0001 T02500217
SPECI KHKS 242139Z 19020G23KT 1 1/4SM +RA SCT023 BKN038 OVC047
24/21 A3016 RMK AO2 PK WND 16030/2104 WSHFT 2115
RAE04B29 P0019 T02390211
SPECI KHKS 242142Z 21019G23KT 1/2SM +RA FG SCT017 BKN038
OVC047 23/21 A3015 RMK AO2 PK WND 16030/2104 WSHFT
2128 LTG DSNT SE RAE04B29 P0039 T02330211
SPECI KHKS 242145Z 21018G25KT 1/4SM +RA FG BKN015 BKN038
OVC047 23/21 A3014 RMK AO2 PK WND 16030/2104 WSHFT
2128 LTG DSNT E AND SE RAE04B29 P0053 T02280211
METAR KHKS 242153Z 20014G25KT 1/2SM +RA FG FEW019 BKN027
OVC045 23/21 A3011 RMK AO2 PK WND 16030/2104 WSHFT
2128 LTG DSNT E AND SE RAE04B29 SLP186 P0073 T02280211
However, during that hour, there was lots of lightning nearby:
The above map is valid from 2100Z-2200Z. The numbers in the upper left corner of each grid,
represents the number of lightning strikes detected in that grid, during the set time. In the same
grid where Hawkins Field is located, there were 114 cloud-to-ground lightning strikes detected!
Yet, KHKS reported no thunderstorm that hour, just LTG DSNT E AND SE. For TS to be
reported, lightning would have to be within 5 miles of the airfield. The next map overlays range
rings upon the previous map, to show that criteria was met:
One can tell that the criteria for TS and VCTS was easily met. Not only that, there was a lightning
bolt which struck the airport:
The valid time of the above map, is 2130Z-2140Z. That was right about the time of the onset of
heavy rain, and IFR conditions, at KHKS. LTGCG AT AP should have been reported, but was not.
The next hour, Hawkins Field did eventually report a thunderstorm:
SPECI KHKS 242156Z 22008KT 3/4SM +RA BR FEW019 OVC031 23/21
A3011 RMK AO2 WSHFT 2140 LTG DSNT E AND SE PRESFR
P0003 T02280211
SPECI KHKS 242205Z 29008KT 270V330 1 1/4SM +RA BR BKN033
OVC080 23/21 A3012 RMK AO2 WSHFT 2140 VIS 3/4V2
1/2 LTG DSNT E AND SE P0012 T02330211
SPECI KHKS 242212Z 34009KT 3SM RA BR SCT036 BKN080 OVC095
23/21 A3012 RMK AO2 WSHFT 2140 LTG DSNT E AND
SE P0013 T02280211
SPECI KHKS 242240Z 28008KT 10SM VCTS -RA FEW065 SCT080 OVC110
23/22 A3010 RMK AO2 WSHFT 2140 LTG DSNT NE-S P0014
T02330217
METAR KHKS 242253Z 28009KT 10SM TS FEW065 SCT090 BKN110 23/22
A3010 RMK AO2 WSHFT 2140 LTG DSNT ALQDS RAE45
TSB52 SLP183 P0014 T02330217
But ALDARS did not begin VCTS until 2240Z, and TS until 2252Z. Meanwhile, there was more
lightning near Hawkins Field:
That chart is valid from 2200Z-2245Z. The bolts in blue are the oldest, and would have occurred not
long after 2200Z. They were located NW-NE AND E. Were they within 5 miles?
2 of them were. The above map is the same data valid 2200-2245Z, with range rings overlaid. It also
shows 2 red-colored bolts. That would have been in the middle of the period, or around 2222Z. So,
during the previous hour, KHKS missed reporting TS and LTGCG AT AP; the 2200-2300Z hour,
KHKS missed reporting TS until 2252Z. That's well over an hour of lead time that could have been
provided to pilots, and resources on the ground; that lightning was striking within 5 miles of the
airport. Considering the LTGCG AT AP occurred no later than 2140Z, that was a negative 1 hour
and 12 minutes of lead time. In other words, TS was not reported until one hour and 12 minutes after
TS criteria was met!
122. Hector Field, Fargo, North Dakota, 24 Jun 2015:
On the evening of the 24th, Hector Field (KFAR) at Fargo, had brief heavy rain pass over the airport:
METAR KFAR 242253Z 34026G38KT 10SM -RA FEW050 BKN070 OVC100
22/11 A3001 RMK AO2 PK WND 33038/2252 RAB46 PRESRR
SLP160 P0000 T02220111
SPECI KFAR 242307Z 35020G29KT 1 3/4SM +RA BR SCT055 OVC075
18/16 A3004 RMK AO2 PK WND 35032/2256 PRESRR P0005
T01780161
SPECI KFAR 242317Z 35012G27KT 3SM +RA BR FEW050 OVC065 17/16
A3005 RMK AO2 PK WND 35032/2256 P0010 T01720156
METAR KFAR 242353Z VRB05KT 10SM -RA FEW035 BKN090 OVC110
18/17 A3002 RMK AO2 PK WND 35032/2256 SLP164 P0019
60019 T01830167 10272 20172 53014
There was no mention of lightning or thunder. Yet, this was the lightning display, valid
from 2245Z-2355Z on the 24th:
So there was some lightning nearby. How much was within 10 miles? 5 miles? The below
map is the same data as above, with 5 and 10-mile range rings added:
So there were 9 lightning bolts within the green 10-mile range ring, that should have triggered
a VCTS. There was also 1 bolt within the red 5-mile range ring, that should have generated a TS.
But neither happened. ALDARS or LAWRS did not even report LTG DSNT in this case. This
was another thunderstorm that was completely missed. The KFAR climatological data base for
"thunderstorm days" will be incorrect because of this- and this is widespread at LAWRS sites.
123. Dannelly Field, Montgomery, Alabama, 24 (25) Jun 2015:
On the evening of 24 June local time (25 Jun UTC), Dannelly Field (KMGM) recorded a wind gust
to 42 knots, 13 minutes after the onset of a VCTS:
METAR KMGM 250053Z 00000KT 10SM CLR 31/25 A3009 RMK AO2 LTG
DSNT E AND S SLP185 T03060250
METAR KMGM 250153Z 00000KT 10SM VCTS CLR 29/26 A3010 RMK
AO2 LTG DSNT E-S SLP189 T02890256
SPECI KMGM 250207Z 08031G42KT 10SM SCT037 28/23 A3014 RMK
AO2 PK WND 06042/0206 LTG DSNT NE-SE PRESRR T02830233
SPECI KMGM 250209Z 07025G42KT 10SM VCTS SQ SCT037 28/21 A3014
RMK AO2 PK WND 06042/0206 LTG DSNT NE-SE T02780206
Most of the lightning from that storm, was E-S:
Some of that lightning was within 5 miles:
The 2 maps above, are valid for the period 0150Z-0230Z. That's the time period of the gust to 42 knots,
and the VCTS. That lightning within 5 miles, should have triggered ALDARS to generate a SPECI for
TS, but that didn't happen. KMGM did not begin a TS until 0240Z:
SPECI KMGM 250241Z 11015G24KT 2SM +TSRA BR BKN037 BKN048
OVC060 22/19 A3015 RMK AO2 PK WND 06042/0206 LTG
DSNT NE-S RAB27 TSB40 LTGIC P0019 T02170194
The time of the lightning within 5 miles, can be narrowed down even further:
The above map begins at 0150Z as well, but its valid time ends at 0205Z. Here is the same data with
range rings overlaid:
There were 2 lightning bolts that should have triggered a TS report, during that 15-minute period. Since
the dots representing the lightning strikes are blue, looking at the color scale it can be seen those were
older bolts. That would place the time of those strikes during the first third of the period; or sometime
before 0155Z. In fact, it can be ascertained that those bolts struck between 0150Z and 0155Z:
Since that is the case, a thunderstorm (TS), and not a thunderstorm in the vicinity (VCTS), should have
been reported at KMGM; no later than 0156Z, but possibly as soon as 0151Z. Both times allow for the
fact that ASOS takes 1 minute to transmit SPECIs. Since airfield refueling and other activities must stop
when lightning is within 5 miles; reporting the TS properly and timely, would have given lead time to
airport workers, before the wind gust to 42 knots struck. The lead time could have been 10-15 minutes.
As it was, lead time for thunderstorm within 5 miles did not occur in this case until well after the strongest
wind occurred.
One last point: once KMGM began a thunderstorm, they reported it as such:
SPECI KMGM 250241Z 11015G24KT 2SM +TSRA BR BKN037 BKN048
OVC060 22/19 A3015 RMK AO2 PK WND 06042/0206 LTG
DSNT NE-S RAB27 TSB40 LTGIC P0019 T02170194
Notice the lightning remark was for in-cloud lightning. The LAWRS observer missed LTGCG that struck
within 5 miles, during the previous 10 minutes:
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Post by tornado on Jun 29, 2015 12:24:24 GMT -5
124. Cecil Field, Jacksonville, Florida, 25 Jun 2015:
Cecil Field in Jacksonville (KVQQ) was reporting clear skies at 1450Z. The next 2 METARS were missing. When the 1750Z METAR
was transmitted, there was heavy rain causing IFR conditions:
METAR KVQQ 251450Z 22006KT 10SM CLR 28/24 A3016
METAR KVQQ 251750Z 21015G31KT 2SM +RA BKN028 30/24 A3011
METAR KVQQ 251850Z 21006KT 7SM BKN075 23/22 A3011
That warranted investigation. Searching the lightning archive for the time period of 1700Z-1900Z, this is what was recorded:
Superimposing range rings on the same data, showed this:
At a minimum, KVQQ should have recorded a VCTS during that time frame.
125. Huntington, West Virginia, 25 Jun 2015:
This site also had heavy rain on the 25th:
METAR KHTS 252251Z 35005KT 7SM -TSRA FEW037 BKN070 OVC110
26/23 A2994
SPECI KHTS 252306Z VRB03G29KT 3SM +RA BR BKN016 BKN030 OVC080
21/20 A2997 RMK AO2 PK WND 27029/2259 TSE2253B2254E05
P0027 T02110200
SPECI KHTS 252309Z 00000KT 1/4SM +RA FG BKN013 BKN030 OVC050
21/20 A2996 RMK AO2 PK WND 27029/2259 TSE2253B2254E05
P0046 T02110200
SPECI KHTS 252316Z 12004KT 10SM SCT030 22/21 A2994 RMK AO2
PK WND 27029/2259 RAEMM TSE2253B2254E05 P0064
T02220206 $
METAR KHTS 252351Z 00000KT 8SM CLR 23/22 A2994
Heavy rain fell even after the thunderstorm ended. But was that really the case?
Since the thunderstorm was said to have ended at 2305Z, the last observed lightning would have been at 2250Z.
But looking at the fist 10 minutes of the 2300Z hour, we find this:
Here is the same data, with range rings superimposed, valid 2300Z-2310Z:
Of the 14 lightning strikes recorded within the same grid as KHTS, all of them were within the red 5-mile range
ring (though one of them was right on the range ring). This means the thunderstorm was ended too early, and was
still in progress during the heavy rain at 2306Z and 2309Z. How close was the lightning?
One bolt struck the airport, just south of the runway, The valid time of the map above is 2300Z-2305Z. Yet KHTS
ended the thunderstorm at 2305Z, when it should not have done so.
126. Huntington, West Virginia, 27 Jun 2015:
Huntington had another issue on the 27th, so this will be treated as a separate case. This proved to be the opposite of what happened in case 125. Huntington began a thunderstorm at 27/0041Z:
METAR KHTS 262351Z 07003KT 10SM FEW045 OVC090 26/20 A2991
SPECI KHTS 270047Z 01012G31KT 3SM TSRA BR SCT018 BKN033 OVC110
20/19 A2992 RMK AO2 PK WND 01031/0039 WSHFT 0033
RAB37 TSB41 P0002
However, lightning data for the period 0000Z-0030Z, showed this:
Here is the same data, valid at the same time, with range rings superimposed:
One can easily see that a VCTS should have been reported during that time; and even a TS within 5 miles.
There were plenty of lightning bolts across the Ohio River in Ohio that should have triggered ALDARS to
begin reporting VCTS; and also bolts in nearby Kentucky. For a better view of the closer lighting, here is
the same data, zoomed in:
Next, here is the closer look, with a red 5-mile range ring partially visible:
2 bolts in Ohio, and 1 lightning bolt in Kentucky, were within 5 miles. That should have triggered ALDARS
to begin a thunderstorm, but did not. KHTS began a thunderstorm at 0041Z; but since the above maps have
0030Z as their latest valid time, at least 11 extra minutes of lead time could have been provided to pilots and
users on the ground. That is, if ALDARS had worked properly, or if LAWRS had observed the lightning.
127. Parkersburg, West Virginia, 26 Jun 2015:
Parkersburg (KPKB) briefly had moderate rain on the 26th:
METAR KPKB 262253Z 02004KT 10SM -RA SCT046 SCT070 BKN120
24/20 A2996 RMK AO2 LTG DSNT SW AND W SLP137 P0002
T02390200
METAR KPKB 262353Z 15005KT 4SM RA BR FEW075 BKN090 OVC110
22/21 A2996 RMK AO2 LTG DSNT SE AND S SLP140 P0014
60016 T02220211 10278 20222 55003
METAR KPKB 270053Z 07004KT 9SM -RA OVC110 22/20 A2997 RMK
AO2 LTG DSNT SE SLP142 P0014 T02220200
No thunder nor lightning remarks appeared in present weather; there was distant lightning reported in remarks.
Yet, this is what the archived lightning data showed, between 2200Z-2400Z (27/0000Z):
Here is the same data, with range rings superimposed:
There were 3 lightning strikes within 10 miles of KPKB, in 3 different directions. Any of those should have triggered
a VCTS to be reported during those 2 hours. That did not happen. Parkersburg missed a thunderstorm in the vicinity
during that time period.
128. Norfolk International Airport, Virginia, 26 Jun 2015:
In case 105, it was demonstrated that Norfolk International Airport (KORF) was in AUTO/TSNO mode, when it had
both arrivals and departures. KORF was again in AUTO/TSNO mode, during obvious bad weather:
METAR KORF 260351Z AUTO 22012KT 10SM CLR 24/20 A2992 RMK AO2 SLP131 T02440200 TSNO
SPECI KORF 260417Z AUTO 27010G30KT 230V310 2 1/2SM R05/6000VP6000FT
+RA SCT026 SCT038 BKN046 22/18 A2997 RMK AO2 PK
WND 28030/0410 WSHFT 0358 RAB13 P0001 T02170178 TSNO
SPECI KORF 260422Z AUTO 27009G29KT 210V350 1 1/4SM R05/2000VP6000FT
+RA BKN022 BKN046 BKN060 21/18 A2997 RMK AO2 PK
WND 28030/0410 WSHFT 0358 RAB13 P0012 T02060178 TSNO
SPECI KORF 260436Z AUTO 21014G17KT 2SM R05/3000VP6000FT +RA
BR FEW026 OVC033 21/18 A2994 RMK AO2 PK WND 28030/0410
WSHFT 0358 RAB13 P0058 T02060183 TSNO
SPECI KORF 260445Z AUTO 18011KT 3SM R05/5500VP6000FT +RA
BR FEW007 OVC035 20/18 A2993 RMK AO2 PK WND 28030/0410
WSHFT 0426 RAB13 P0066 TSNO
METAR KORF 260446Z AUTO 18011KT 3SM R05/5500VP6000FT +RA
BR FEW007 OVC037 20/18 A2993 RMK AO2 PK WND 28030/0410 WSHFT 0426 RAB13 SLP136 P0067 T02000183 403110200 TSNO
SPECI KORF 260454Z AUTO 19009KT 3SM R05/6000VP6000FT +RA
BR BKN007 OVC041 21/19 A2994 RMK AO2 WSHFT 0435
P0006 T02060189 TSNO
Going by the lightning data from 0400Z-0500Z, some of those reports should have been +TSRA; but with
KORF being in TSNO mode, no TS data would be forthcoming.
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Post by tornado on Jun 29, 2015 13:36:54 GMT -5
129. Newport News, Virginia, 26 Jun 2015:
On the evening of 26 Jun, Newport News (KPHF) reported a thunderstorm not long before the tower closed:
METAR KPHF 260254Z 18007KT 10SM CLR 25/22 A2992 RMK AO2 LTG
DSNT W-N SLP130 T02500222 56017
SPECI KPHF 260326Z 15008KT 10SM VCTS CLR 25/22 A2990 RMK
AO2 LTG DSNT ALQDS T02500217
SPECI KPHF 260344Z 26024G39KT 2 1/2SM TSRA BR SQ FEW024 SCT036
BKN050 22/21 A2995 RMK AO2 PK WND 24039/0340 LTG
DSNT ALQDS RAB40 TSB33 PRESRR P0011 T02220206
SPECI KPHF 260351Z AUTO 24022G33KT 3/4SM +TSRA BR SCT022
BKN036 BKN050 21/20 A2993 RMK AO2 PK WND 24039/0340
LTG DSNT ALQDS RAB40 TSB33 P0029
METAR KPHF 260354Z AUTO 24021G29KT 3/4SM +TSRA BR BKN022
BKN036 OVC050 21/20 A2992 RMK AO2 PK WND 24039/0340
WSHFT 0338 LTG DSNT ALQDS RAB40 TSB33 SLP132 P0038
T02110200
The start time of the VCTS was 0326Z; for the TS, the begin time was 0333Z.
Lightning data showed this, for the 15 minutes preceding the official start of the VCTS:
Here is the same data, with range rings overlaid. The valid time is 0310Z-0325Z:
It's hard to see the lightning strike within 5 miles on the above map, so let's zoom in:
A lightning bolt struck just west of Interstate 64, but east of U.S. Highway 60; within the red
5-mile range ring. So ALDARS was late at reporting TS. But it was also late at reporting VCTS:
The maps above and below, are set for the 5-minute window of 0300Z-0305Z:
Since there was a lightning strike within the green 10-mile range ring (about 7.5 miles from
KPHF), ALDARS was late in beginning a VCTS. Since ALDARS detected lightning within
10 miles at 0326Z, that would make it 21 minutes late. That would have been 21 extra minutes
of lead time for ground personnel, had ALDARS worked properly. But it takes lightning
within 5 miles to suspend some ground activities, such as refueling aircraft.
The maps above and below, are set for the 5-minute period of 0325Z-0330Z.
There were 3 lightning bolts that struck within 5 miles during that 5-minute period; to the NE, SE
and SW. Let's zoom in:
Using the color scale on the right side of the map, the blue bolt to the SE of KPHF was the oldest. It occurred
at 0325Z, certainly no later than 0326Z. That was still 7 minutes before the official beginning time of the
thunderstorm. It was also the same time as the SPECI to start a VCTS. The troubling thing was, the SPECI to
start the TS was not transmitted until 0344Z! The gust to 39 knots occurred at 0340Z. So, if ALDARS had
worked properly and detected the lightning on time; users on the ground would have had more lead time,
and personnel would have had more time to take cover. As it was, it went from VCTS CLR, to TS reported
4 minutes after a G39KT occurred, also with moderate rain.
130. Panama City, Florida, 26 Jun 2015:
Panama City (KECP) recorded a VCTS during the morning of the 26th:
METAR KECP 260953Z AUTO 21006KT 10SM FEW033 SCT060 27/22
A3000 RMK AO2 LTG DSNT W SLP170 T02670217
SPECI KECP 261047Z 28013KT 1 1/2SM +RA BR FEW017 SCT023 BKN028
25/23 A3004 RMK AO2 LTG DSNT NW RAB43 P0001
METAR KECP 261053Z 29009KT 1/2SM +RA FG FEW017 BKN021 BKN028
24/23 A3004 RMK AO2 LTG DSNT NW RAB43 SLP182 P0003
T02440233
SPECI KECP 261059Z 31008KT 1SM VCTS RA BR FEW017 BKN031 OVC044
24/23 A3004 RMK AO2 LTG DSNT NW P0002 T02440233
SPECI KECP 261123Z 36005KT 6SM -RA BR FEW025 BKN036 OVC110
24/23 A3004 RMK AO2 LTG DSNT SW AND W P0009 T02440233
SPECI KECP 261148Z 00000KT 10SM VCTS FEW028 SCT033 BKN095
24/23 A3005 RMK AO2 LTG DSNT SE-W RAE33 P0016
METAR KECP 261153Z 00000KT 8SM VCTS -RA FEW027 SCT033 OVC100
24/23 A3005 RMK AO2 LTG DSNT SE-W RAE33B52 SLP186
P0017 60020 70020 T02440233 10272 20244 51016
But, the VCTS did not begin until 1059Z. That was after heavy rain had already been falling. But during the period
of inclement weather, the lightning data showed this:
That chart was valid for the period of 1040Z-1200Z on the 26th. So was this one:
So we see that there were 6 lightning strikes within the red 5-mile range ring, that were not reported at KECP. The
site reported VCTS, but not TS. Also, VCTS did not officially begin until 1059Z; but earlier lightning data shows this:
That chart was valid for the period 1000-1040Z. Here is the same data, with range rings superimposed:
There was lightning WSW-NW, within the green 10-mile range ring, during that period. All of that lightning was prior
to the official start time of the VCTS; which means ALDARS was late in beginning the VCTS. The oldest bolts among
those that struck within 10 miles, were the 2 reddish bolts to the WNW. Using the color scale, red is just past the halfway
mark of the time frame. Since that is 1000Z-1040Z, we can estimate the time of those lightning strikes to be in the 1020Z-
1025Z range. That is certainly well before KECP began a VCTS. So an additional 34 minutes of lead time could have
been provided to users regarding the VCTS; and TS occurred at KECP when none was reported.
131. Gainesville, Florida, 26 Jun 2015:
On 26 Jun, Gainesville (KGNV) reported a thunderstorm:
METAR KGNV 261553Z VRB04KT 10SM BKN037 32/22 A3009 RMK AO2
LTG DSNT SW AND W SLP185 T03170222
SPECI KGNV 261633Z 26024G31KT 1 1/2SM VCTS -RA BKN038 BKN050
BKN085 26/22 A3011 RMK AO2 PK WND 25031/1628 LTG
DSNT N AND S AND SW RAB31 PRESRR P0000 T02560217
SPECI KGNV 261637Z 27019G31KT 1/2SM VCTS +RA FG FEW025 SCT038
BKN050 23/22 A3012 RMK AO2 PK WND 25031/1628 WSHFT
1623 LTG DSNT N AND S AND SW RAB31 PRESRR P0006
T02330217
SPECI KGNV 261646Z 26004KT 1SM +TSRA BR BKN040 BKN050 OVC110
23/22 A3012 RMK AO2 PK WND 25031/1628 WSHFT 1623
LTG DSNT N AND S RAB31 TSB46 P0033 T02330217
METAR KGNV 261653Z 26003KT 1SM TSRA BR FEW036 BKN050 OVC110
23/22 A3012 RMK AO2 PK WND 25031/1628 WSHFT 1623
LTG DSNT N AND NE AND S RAB31 TSB46 SLP198 P0038
T02330222
The start time for the VCTS was recorded as 1633Z; while the start time for the TS was 1646Z.
Lightning data showed that those times were late.
The 3 maps in this case are all valid for the period 1600Z-1640Z on 26 Jun. Here is the same data
with range rings superimposed:
Within the red 5-mile range ring, 4 lightning strikes can be seen. 2 bolts are shown in yellow, and 2
in red. The yellow bolts would have occurred right before 1640Z; the red bolts would have occurred
closer to 1620Z. That is prior to both the TS and the VCTS; therefore, both times calculated by
ALDARS were incorrect. Here is a closer view of the situation:
TS N should have been in remarks, even before ALDARS at KGNV took the SPECI to begin a VCTS.
Users on the ground should have been warned of lightning within 5 miles around 1620Z. As it was, users received a negative 26 minutes of warning for lightning within 5 miles of KGNV.
132. Lakefront Airport, New Orleans, Louisiana, 26 Jun 2015:
On 26 Jun, Lakefront Airport (KNEW) recorded moderate rain, with gusty winds, at 1821Z:
METAR KNEW 261753Z 19007KT 10SM SCT031 31/22 A3005 RMK AO2
SLP168 60000 T03110222 10311 20283 58014
SPECI KNEW 261821Z 24017G25KT 1 3/4SM RA SCT028 SCT050 BKN070
28/24 A3006 RMK AO2 RAB08 P0008 T02830239
SPECI KNEW 261836Z 20006KT 10SM -RA FEW023 SCT035 BKN070
28/21 A3004 RMK AO2 RAB08 P0019 T02780206
METAR KNEW 261853Z 20006KT 10SM FEW037 FEW100 28/24 A3003
RMK AO2 RAB08E41 SLP162 P0019 T02830239
However, here was the lightning activity around KNEW between 1800Z and 1900Z:
Here is the same data, with range rings superimposed:
There were 2 lightning strikes, out over Lake Pontchartrain, in almost the same place; that were
both within the red 5-mile range ring. That should have triggered a TS report at KNEW, but did
not. Note there were also other lightning bolts that struck within the green 10-mile range ring.
That should have triggered a VCTS; yet, ALDARS did not do so. There were also many lightning
bolts that struck to the east, that were within 30 miles; the grid counted detected 148 lightning
strikes in that sector! Yet, not even DSNT LTG was recorded at KNEW during that hour. ALDARS
failed, or LAWRS observers at KNEW didn't detect any lightning either.
133. North Perry Airport, Hollywood, Florida, 26 Jun 2015:
On 26 Jun, North Perry Airport (KHWO) reported this:
METAR KHWO 261653Z 14010KT 10SM FEW060 32/20 A3009 RMK AO2
SLP190 T03170200
METAR KHWO 261753Z 31012KT 10SM FEW030 SCT038 BKN048 27/22
A3013 RMK AO2 SLP201 T02670222 10333 20267 53003
METAR KHWO 261853Z 10003KT 10SM FEW029 27/25 A3009 RMK AO2
RAB1756E35 SLP190 P0004 T02720250
METAR KHWO 261953Z AUTO 09007KT 10SM CLR 31/25 A3007 RMK
AO2 SLP182 T03060250 TSNO
Yet, lightning data between 1700Z and 1800Z, showed this:
Here is the same data, with range rings added:
There were several lightning strikes within the green 10-mile range ring around KHWO; yet,
no VCTS was reported. There were also 2 lightning strikes within the red 5-mile range ring,
to the west of the airport; yet, no TS was reported. KHWO missed a thunderstorm that hour!
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Post by tornado on Jun 30, 2015 10:19:04 GMT -5
134. Easterwood Field, College Station, Texas, 27 Jun 2015:
The College Station (KCLL) ASOS was in AUTO mode, the hour before ATC opened the tower and signed on:
METAR KCLL 271153Z AUTO 25006KT 10SM SCT017 BKN024 26/24
A3002 RMK AO2 LTG DSNT NW SLP161 T02560239 10267
20256 53013
SPECI KCLL 271208Z AUTO 26008KT 10SM FEW017 SCT024 26/24
A3003 RMK AO2 LTG DSNT NW T02560239
SPECI KCLL 271238Z AUTO 32007KT 10SM SCT016 BKN028 OVC040
24/22 A3004 RMK AO2 LTG DSNT N AND NW T02440222
METAR KCLL 271253Z 31007KT 10SM BKN018 OVC026 24/22 A3005
RMK AO2 LTG DSNT N AND NW SLP170 T02390217
But lightning data for the period 1200Z-1300Z showed this:
Here is the same data, with added range rings:
Since there was lightning within the green 10-mile range ring during that hour, ASOS should have generated a SPECI
for VCTS. It did not. ASOS was not in TSNO mode, so ALDARS missed that VCTS.
135. Athens, Georgia, 27 Jun 2015:
Athens Airport (KAHN) had heavy rain (showers), from 1829Z-1837Z:
METAR KAHN 271751Z 24008KT 10SM SCT035 BKN045 BKN050 31/21
A2987 RMK AO2 SLP106 T03110211 10328 20239 58020
SPECI KAHN 271829Z 30014G25KT 1 1/2SM +RA FEW031 BKN037 OVC048
26/23 A2987 RMK AO2 VIS 3/4V5 RAB22 P0002 T02610228
SPECI KAHN 271832Z 28012G25KT 3/4SM +RA BR SCT025 BKN037
OVC048 24/22 A2989 RMK AO2 RAB22 PRESRR P0008
T02440222
SPECI KAHN 271837Z VRB05G21KT 1/2SM +RA FG BKN020 BKN037
OVC048 23/22 A2988 RMK AO2 RAB22 P0032 T02330217
SPECI KAHN 271844Z 00000KT 1SM -RA BR SCT018 BKN037 OVC080
23/22 A2988 RMK AO2 VIS 1/4V5 RAB22 P0037 T02330217
SPECI KAHN 271847Z 00000KT 3SM -RA BR SCT018 BKN037 OVC080
24/22 A2988 RMK AO2 RAB22 P0037
METAR KAHN 271851Z 31003KT 7SM -RA SCT020 BKN040 OVC100 24/22
A2988 RMK AO2 RAB22 SLP110 P0037 T02390222
METAR KAHN 271951Z VRB04KT 6SM -RA BR FEW045 BKN090 OVC110
24/23 A2988 RMK AO2 SLP111 P0001 T02440228
Between 1800Z-1900Z, this was the lightning display around Athens:
Here is that data with range rings superimposed:
So we see that there were 3 lightning strikes, NE-SE of KAHN, within the red 5-mile range ring. That should
have triggered ALDARS (or ATC) to take a SPECI for TS, but no TS was recorded that hour.
We can narrow down the time of those lightning strikes:
Those 3 bolts struck between 1840Z and 1845Z, which is the valid time of the map above. Looking at the color
scale, it can even be estimated that the bolts hit from about 1841-1843Z. Now, there was heavy rain and poor
visibility (1/2 to 1SM) around that time; but ALDARS detects lightning by electrical impulses, so the rain and
poor visibility wouldn't affect it. A human being ought to be able to hear thunder at that range, even with heavy
rain and poor visibility. But since ATC does not go outside to listen for thunder, they missed that TS as well.
136. Newport News, Virginia, 27 Jun 2015:
Newport News Airport (KPHF) had ended a thunderstorm at 1959Z. But the hour preceding the 2154Z METAR,
there was heavy rain. The hourly rainfall total was .62":
METAR KPHF 272054Z 17007KT 10SM -RA FEW027 BKN070 OVC120
24/21 A2979 RMK AO2 LTG DSNT NW TSE1959 SLP085
P0005 60010 T02390211 56018
SPECI KPHF 272115Z 21008KT 1 1/2SM +RA BR FEW035 BKN070 OVC110
23/22 A2980 RMK AO2 LTG DSNT N AND NW P0010 T02330217
SPECI KPHF 272126Z 00000KT 1/2SM +RA FG SCT033 BKN050 OVC095
23/22 A2979 RMK AO2 LTG DSNT ALQDS P0027 T02280217
SPECI KPHF 272137Z 33004KT 2SM +RA BR FEW023 BKN031 OVC060
23/22 A2979 RMK AO2 LTG DSNT S P0031 T02280217
SPECI KPHF 272145Z 00000KT 3/4SM +RA BR FEW016 BKN029 OVC055
23/22 A2979 RMK AO2 P0041 T02280217
METAR KPHF 272154Z 00000KT 1/4SM +RA FG FEW013 BKN022 OVC050
22/22 A2978 RMK AO2 SLP082 P0062 T02220217
Here was the lightning situation around KPHF for the period 2100Z-2130Z:
Here is the same data, with range rings overlaid:
There were 2 lightning strikes during that period, that fell within the red 5-mile range ring. They were
both about 3 miles from the airport. Sometime during that hour, a thunderstorm should have been
reported, but was not. The .62" of rainfall was not just +RA, but +TSRA.
137. Erie, Pennsylvania, 27 Jun 2015:
The Erie Airport (KERI) was windy between 21Z and 23Z on the 27th, but made no mention of lightning activity:
METAR KERI 272051Z 14017G26KT 10SM FEW050 BKN065 OVC085 19/14
A2965 RMK AO2 PK WND 14028/2011 RAE33 SLP037 P0000
60001 T01890144 56025
METAR KERI 272151Z 14014G25KT 10SM FEW029 BKN065 OVC100 18/14
A2963 RMK AO2 PK WND 14026/2128 SLP032 T01830144
METAR KERI 272251Z 14015G29KT 10SM FEW048 BKN080 OVC090 18/14
A2962 RMK AO2 PK WND 15029/2242 RAB11E46 CIG 065
NE SLP029 P0001 T01830144
Between 2100Z and 2230Z, this was the lightning display around Erie:
Range rings added to the above data, show this:
Since there were several lightning strikes inside of the green 10-mile range ring, a VCTS should have been
recorded sometime between 2100Z-2230Z. But also, there were 5 lightning strikes within the red 5-mile
range ring; that should have triggered a TS to be reported at KERI during that 90-minute period. But, none
was reported then. KERI missed a thunderstorm during that time.
138. Baton Rouge, Louisiana, 27 Jun 2015:
Baton Rouge Airport (KBTR) had good weather at 1953Z. By 2053Z, thunderstorms were approaching. It appears
that ATC put ASOS into AUTO mode- but then sent a COR removing AUTO. But they forgot to remove the TSNO
remark. So, with no thunderstorm information at 2053Z, a thunderstorm struck the airfield with little warning:
METAR KBTR 271953Z 23011KT 10SM SCT035 31/24 A2996 RMK AO2
SLP143 T03060244
METAR KBTR 272053Z COR 25010KT 10SM SCT030 32/23 A2995 RMK
AO2 SLP140 T03170233 56014 TSNO
SPECI KBTR 272131Z 29026G35KT 1/2SM +TSRA FG BKN032 24/22
A2996 RMK AO2 PK WND 28035/2129 RAB20 TSB31 PRESRR
P0003 T02440222 RVRNO
Should there have been more warning? The following map is valid from 2100Z-2130Z on 27 Jun:
Here is the same data, with range rings superimposed:
The 3 lightning bolts to the N-NE of the airfield, were younger (as represented by their yellow color)
and may have been the ones to trigger the TSB31. But there were older bolts that could have been
reported, if ALDARS was turned on, or if ATC had noticed. To the west of KBTR, there were other
lightning strikes within the green 10-mile range ring. Any or all of those should have triggered a
VCTS. How early would that have been?
The above chart is valid for the period 2105Z-2115Z on 27 Jun. It shows 4 lightning bolts within the
green 10-mile range ring, that should have generated a SPECI to begin VCTS. That didn't happen.
But if ALDARS/LAWRS had recorded a VCTS that early, pilots and users on the ground would have
had more lead time for the thunderstorm that produced the heavy rain, and wind gust to 35 knots. In fact, the lead time would have been 16 minutes, instead of zero minutes. With the regards to the wind gust to 35 knots, the lead time was -2 minutes, since the gust occurred at 2129Z. |
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Post by tornado on Jun 30, 2015 12:47:29 GMT -5
139. Tupelo, Mississippi, 27 Jun 2015:Either ALDARS or the LAWRS observer at Tupelo Airport (KTUP), detected distant lightning between 0350Z and 0500Z: METAR KTUP 270353Z 25008G16KT 10SM FEW060 27/24 A2990 RMK AO2 LTG DSNT N SLP119 T02720244 METAR KTUP 270453Z 26006KT 10SM FEW060 27/23 A2989 RMK AO2 LTG DSNT N-E SLP114 T02670233 METAR KTUP 270553Z 25008KT 240V310 10SM BKN044 26/23 A2988 RMK AO2 SLP113 T02610233 10317 20261 403330233 58000 This was the lightning data for the period 0430Z-0600Z:  Here is the same data, with added range rings:  There was plenty of lightning, 10-30 miles away to the east. But there were also 2 bolts that struck to the E-SE, that were within the green 10-mile range ring. That should have triggered a VCTS, but did not. The time of the nearest lightning strike can be narrowed down:  The above map is valid for 0445Z-0450Z on June 27th. But the 0453Z METAR did not contain a VCTS. This was a case of a missed thunderstorm in the vicinity of Tupelo. 140. Key Field, Meridian, Mississippi, 27 Jun 2015:Key Field (KMEI) briefly went IFR on 27 Jun, due to rain, from 1454Z-1458Z: SPECI KMEI 271440Z 26003KT 10SM BKN014 OVC020 27/23 A2998 RMK AO2 T02670233 SPECI KMEI 271454Z VRB03KT 2 1/2SM R01/2400VP6000FT -RA BR OVC012 26/24 A2998 RMK AO2 RAB45 P0003 METAR KMEI 271458Z 00000KT 8SM -RA OVC012 26/24 A2998 RMK AO2 RAB45 SLP147 P0003 60003 T02560239 51010 Lightning data for the period of 1450Z-1530Z showed this:  Here is the same data, with range rings overlaid:  There were lightning strikes within the green 10-mile range ring. That indicates a thunderstorm was in the vicinity; but one was not reported at KMEI during that time. The IFR visibility due to rain, and low RVR, should have clued in ATC to look for lightning. ALDARS, if installed, missed that VCTS.141. Orlando-Sanford Airport, Florida, 27 Jun 2015:ALDARS/LAWRS at Orlando-Sanford Airport (KSFB) detected distant lightning at these times: METAR KSFB 272153Z 28011KT 10SM SCT055 34/22 A2997 RMK AO2 SLP146 T03440217 METAR KSFB 272253Z 27013KT 10SM FEW055 34/21 A2998 RMK AO2 LTG DSNT S AND SW SLP152 T03390206 METAR KSFB 272353Z 21010KT 10SM SCT060 32/21 A3000 RMK AO2 LTG DSNT NE AND E SLP156 T03170206 10356 20317 53011 Lightning data from 2200Z-2300Z showed this:  With added range rings, the data reveals this:  Since there were 2 lightning bolts within 10 miles, a VCTS should have been reported. Also, since there was 1 lightning bolt within 5 miles, TS should have been reported. But neither VCTS nor TS was reported. The closest bolt actually struck between 2200Z- and 2205Z:  Yet, that went undetected. 142. Ft. Lauderdale Executive Airport, Florida, 27 Jun 2015:This airport (KFXE) had an interesting day: METAR KFXE 271353Z 18005KT 10SM CLR 29/24 A3009 RMK AO2 SLP190 T02940239 SPECI KFXE 271439Z 27007KT 10SM FC SCT020 30/23 A3009 RMK FUNNEL CLOUD B36 1NM SE AO2 T03000233 SPECI KFXE 271450Z 10SM TS SCT020 BKN100 29/22 A3009 RMK FUNNEL CLOUD B36 1NM SE FUNNEL CLOUD E49 AO2 TSB50METAR KFXE 271453Z 18009G18KT 150V210 10SM TS SCT020 BKN100 28/21 A3010 RMK FUNNEL CLOUD B36 1NM SE FUNNEL CLOUD E49 AO2 TSB50 SLP195 T02830206 51012 Clear skies, turned into a funnel cloud 43 minutes later! Tornadic activity is usually produced by mature thunderstorms. In this case, a funnel cloud was reported before the thunderstorm. Could there have been more warning that something was up? Certainly there was some lightning in the area that hour:  The maps above and below are valid for the period 1400Z-1500Z on 27 Jun:  So there was certainly lightning within 10 miles. But when did that start?  The above map is valid from 1430Z-1435Z. It shows that a VCTS could have been reported that early. Since the lightning bolt 8 miles to the west is purple in color, it would have struck about 1431Z. Perhaps a few minutes extra warning that a VCTS was in progress, would have helped users to anticipate that other thunderstorm hazards could follow- such as funnel clouds.
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Post by tornado on Jun 30, 2015 15:27:13 GMT -5
143. Crystal Airport, Minneapolis, Minnesota, 28 Jun 2015:
Minneapolis-Crystal (KMIC) had fair weather at 1953Z. But once it began raining, KMIC put ASOS into AUTO mode
for the next 2 reports; ASOS was also in TSNO mode, meaning no thunderstorm data would be provided. By 2111Z, it
was IFR due to heavy rain. Winds had gusted to 29 knots earlier:
METAR KMIC 281953Z 31008KT 10SM SCT045 BKN055 27/16 A2977
RMK AO2 SLP077 T02670156
METAR KMIC 282053Z AUTO 02021G29KT 8SM -RA BKN043 BKN055
OVC095 23/17 A2978 RMK AO2 PK WND 04029/2052 RAB07
SLP082 P0001 60001 T02330172 55005 TSNO
SPECI KMIC 282102Z AUTO 03016G28KT 1 3/4SM RA FEW035 BKN043
OVC070 21/18 A2981 RMK AO2 PK WND 02027/2056 PRESRR
P0007 T02060178 TSNO
SPECI KMIC 282111Z 05011G20KT 3/4SM +RA BR BKN028 BKN043
OVC070 19/17 A2982 RMK AO2 PK WND 02027/2056 PRESRR
P0031 T01940172
SPECI KMIC 282121Z 00000KT 2 1/2SM -RA BR BKN036 BKN046 OVC070
19/17 A2982 RMK AO2 PK WND 02027/2056 P0033 T01940172
SPECI KMIC 282128Z 00000KT 7SM -RA SCT036 BKN046 OVC090 19/17
A2982 RMK AO2 PK WND 02027/2056 P0034 T01940172
METAR KMIC 282153Z 25006KT 10SM FEW038 BKN100 20/18 A2981
RMK AO2 PK WND 02027/2056 RAE41 SLP093 P0034 T02000178
Since that looked like it could have been a thunderstorm, it warranted investigation. Lightning data for the period of 2100Z-2200Z was as such:
Below is the same data, with range rings added:
There was not only plenty of lightning within the green 10-mile range ring; there were 4-5 lightning strikes within the red 5-mile
range ring. KMIC should have reported TS that hour, but did not. ASOS ought not operate in TSNO mode in such cases!
144. Jefferson City, Missouri, 27 (28) Jun 2015:
Jefferson City Airport (KJEF) had breezy and partly to mostly cloudy conditions:
METAR KJEF 282053Z 22013G17KT 10SM SCT065 BKN100 29/19 A2981
RMK AO2 SLP082 T02890189 55028
METAR KJEF 282153Z 22011KT 10SM SCT055 SCT075 29/19 A2977
RMK AO2 SLP068 T02940189
METAR KJEF 282253Z 24015G20KT 10SM SCT050 BKN065 BKN080 28/19
A2977 RMK AO2 PK WND 22026/2210 SLP066 T02830189
But there was no mention of lightning in those reports. Lightning data between 2100Z and 2300Z, showed this:
Here is the same data, with range rings superimposed:
There were several lightning bolts that struck within the green 10-mile range ring during that 2-hour window. But ALDARS
did not record even LTG DSNT during that time. VCTS should have been reported, and SPECIs taken and disseminated.
The time of the closest lightning bolt was between 2235Z-2240Z:
That bolt was just within the 5-mile range. KJEF missed at least a VCTS on 28 Jun.
145. Baton Rouge, Louisiana, 27 (28) Jun 2015:
Baton Rouge Airport (KBTR) had some heavy rain, not long before the control tower closed for the evening:
METAR KBTR 280453Z 34005KT 10SM -RA BKN027 BKN043 OVC050
24/22 A3000 RMK AO2 RAB46 SLP156 P0000 T02390222
SPECI KBTR 280519Z 00000KT 1 3/4SM +RA BR BKN013 OVC026 24/22
A3000 RMK AO2 RAE0455B13 P0001 T02390222
SPECI KBTR 280529Z 13003KT 2 1/2SM -RA BR SCT011 BKN023 OVC030
23/23 A3000 RMK AO2 RAE0455B13 P0020 T02330228
SPECI KBTR 280531Z 12004KT 7SM -RA FEW011 SCT023 BKN030 23/23
A3000 RMK AO2 RAE0455B13 P0020 T02330228
SPECI KBTR 280550Z 13004KT 6SM RA BR FEW006 BKN034 BKN070
24/23 A2999 RMK AO2 RAE0455B13 P0021
METAR KBTR 280553Z 10003KT 6SM -RA BR FEW006 BKN034 24/23
A2999 RMK AO2 RAE0455B13 SLP154 P0023 60023 T02390228
10256 20233 403280228 51003
SPECI KBTR 280631Z AUTO 24006KT 10SM BKN025 BKN039 BKN049
24/23 A2998 RMK AO2 RAE21 P0000 T02390228 TSNO
During the period of heavy rain, the lightning display between 0500Z and 0600Z was as follows:
Here is the same data, with range rings overlaid upon it:
ALDARS or LAWRS missed a lot of lightning! There were 24 lightning strikes in the same grid where
KBTR is located; 22 of those were within the red 5-mile range ring. ALDARS also missed a lot of
lightning that would have been VCTS criteria. Thus, the +RA should have been reported as +TSRA.
After ATC logged off ASOS and went home, there was the closest lightning strike yet:
That occurred between 0610Z-0615Z. ALDARS had no chance to detect that strike on Veterans Memorial Blvd,
because ASOS had been placed in AUTO/TSNO mode. Yet, before ATC went home for the evening, there was
a missed thunderstorm.
146. Lakefront Airport, New Orleans, Louisiana, 28 Jun 2015:
Lakefront Airport (KNEW) had 2 issues on the 28th. First, there was a bit of rain and a wind shift between 0100Z
and 0200Z:
METAR KNEW 280053Z 32015KT 10SM FEW041 31/23 A2997 RMK AO2
SLP142 T03060228
SPECI KNEW 280148Z 22013KT 6SM -RA SCT038 BKN070 OVC110 27/22
A2999 RMK AO2 WSHFT 0128 RAB34 P0003
METAR KNEW 280153Z 22009KT 6SM -RA SCT034 BKN070 OVC100 26/22
A2999 RMK AO2 WSHFT 0128 RAB34 SLP149 P0003 T02610217
Lightning data between 0100Z-0200Z, showed this:
The same data, with range rings superimposed, showed this:
Just like up the river in Baton Rouge, Lakefront Airport missed a lot of lightning! Recall that there were no lightning
remarks at all between 0053Z-0153Z at KNEW. Yet lightning data showed 54 strikes in the grid where KNEW is
located; plus 84 strikes in the grid to the east. Many of the lightning strikes within those grids, were within the red 5-mile
range ring. Thunderstorm (TS) clearly should have been reported at KNEW that hour, but was not. Many more strikes
met the criteria for VCTS as well.
Zooming in on lightning data, with the same valid time, it can be seen that 2 lightning bolts struck airport property:
Also, KNEW had problems later the same day, when there was a bit more light rain:
METAR KNEW 281953Z 28005KT 10SM -RA FEW024 SCT055 BKN095
28/23 A3001 RMK AO2 RAB51 SLP156 P0000 T02830233
METAR KNEW 282053Z 25008KT 10SM FEW090 29/23 A3001 RMK AO2
RAE03 SLP155 P0000 60000 T02890233 56014
There was no mention of lightning in either of the METARs above. But, between 2000Z and 2030Z, lightning data showed this:
This was the data from the same half hour period, with range rings overlaid:
So there were 3 lightning strikes, from SE-S, that ALDARS missed during that half hour. This was the 2nd missed thunderstorm in less than 24 hours at this site! |
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Post by tornado on Jul 1, 2015 15:10:58 GMT -5
147. Cecil Field, Jacksonville, Florida, 28 Jun 2015:
Cecil Field (KVQQ) is a level C LAWRS site. It doesn't seem to report SPECIs, or remarks.
From 1700Z-1800Z, this was the lightning display:
The same data is presented below, with range rings:
The reports coming out of KVQQ, were as follows:
METAR KVQQ 281650Z 27010KT 10SM BKN042 33/23 A2998
METAR KVQQ 281750Z 24006KT 10SM SCT001 23/23 A3000
METAR KVQQ 281850Z 20004KT 10SM CLR 27/23 A2998
The SCT001 at 1750Z, could have been scud clouds (cumulus fractus) from the nearby thunderstorm.
There were at least 19 lightning strikes within the red 5-mile range ring around KVQQ that went
unreported. There were many additional strikes within the green 10-mile range ring, that did not
trigger a SPECI for VCTS. This site missed that thunderstorm. But later, they missed another:
The above map was valid for the period 2200-2330Z on the 28th. Here is the same data, with
added range rings:
That time, there were 6 lightning strikes within the 5-mile range ring. Yet, these were the reports
coming out of KVQQ for that time:
METAR KVQQ 282150Z 34008KT 10SM BKN037 27/23 A2999
METAR KVQQ 282250Z 04005KT 10SM BKN035 22/22 A3000
The closest lightning bolt struck between 2230 and2235Z:
That bolt struck right off the runway, or perhaps right on it! Yet not even that lightning strike,
triggered any kind of thunderstorm report at Cecil Field. 2 thunderstorms were missed that day!
148. Ft. Lauderdale Executive Airport, Florida, 28 Jun 2015:
Further south in Florida, Ft. Lauderdale Executive Airport (KFXE) reported decent weather:
METAR KFXE 281753Z 12011KT 10SM SCT032 SCT060 33/23 A3004
RMK AO2 SLP176 60000 T03280233 10333 20283 58014
METAR KFXE 281853Z 14013KT 10SM SCT042 SCT049 32/22 A3003
RMK AO2 SLP171 T03220222
METAR KFXE 281953Z 20011KT 10SM SCT035 SCT100 BKN250 32/22
A3003 RMK AO2 SLP172 T03220222
However, lightning data between 1800Z-1900Z, showed this:
Here is the same data with range rings superimposed:
There were 4 lightning strikes within the red 5-mile range ring. Those should have generated a
SPECI for TS, but that didn't happen. Additional strikes to the south, were within 10 miles.
ALDARS should have triggered ASOS (or LAWRS) to take a SPECI for VCTS, but that did
not happen either. The closest lightning bolt, can be determined to have struck between
1805-1810Z:
That bolt was not far to the SE of airport property. Yet, even that lightning strike did not trigger
a SPECI for TS! ALDARS/LAWRS missed that thunderstorm at KFXE.
149. Lawrence, Massachusetts, 28 Jun 2015:
Thunderstorms in the northeastern U.S., i.e., New England; are not as strong as in the southeast or Midwest.
But they do occur. Lawrence (KLWM) had rainy, windy conditions on the morning of 28 Jun:
METAR KLWM 281054Z 06019G27KT 2 1/2SM -RA BR BKN008 OVC014
14/13 A2988 RMK AO2 PK WND 05027/1054 SLP117 P0004
T01390128
SPECI KLWM 281144Z 06018G28KT 2SM -RA BR BKN010 BKN017 OVC023
14/13 A2988 RMK AO2 PK WND 05030/1129 SFC VIS
3 CIG 007V013 P0006 T01390128
SPECI KLWM 281151Z 05022G34KT 2SM +RA BR SCT008 BKN014 OVC021
14/12 A2987 RMK AO2 PK WND 05034/1149 P0011
METAR KLWM 281154Z 06015G34KT 1 3/4SM +RA BR SCT008 BKN014
OVC021 14/12 A2987 RMK AO2 PK WND 05034/1149 TWR
VIS 2 SLP115 P0013 60061 70088 T01390122 10144
20139 55017
SPECI KLWM 281208Z 06017G36KT 2SM RA BR BKN010 BKN016 OVC024
14/12 A2987 RMK AO2 PK WND 06036/1200 P0009 T01390122
SPECI KLWM 281215Z 05022G31KT 2SM RA BR BKN008 BKN016 OVC026
14/12 A2986 RMK AO2 PK WND 06036/1200 SFC VIS
2 1/2 P0011 T01390122
METAR KLWM 281254Z 06018G26KT 2SM RA BR BKN009 OVC013 14/12
A2985 RMK AO2 PK WND 06036/1200 SFC VIS 2 1/2
CIG 006V010 SLP107 P0017 T01390122
So moderate to heavy rain was falling during that time. But, lightning data for the period 1100Z-1300z,
showed this:
Here is the same 2-hour block of data, with added range rings:
So there were 2 lightning strikes that were missed, and not reported. The closest bolt struck between
1120-1125Z:
Even in New England, ALDARS or LAWRS sometimes missed reporting thunderstorms.
150. Flagstaff, Arizona, 29 Jun 2015:
On the other side of the USA, Flagstaff (KFLG) was experiencing "monsoon" conditions, meaning that
the weather was coming from the east, not the west.
METAR KFLG 291857Z 28005KT 10SM OVC080 27/07 A3034 RMK AO2
SLP156 T02720072
SPECI KFLG 291857Z 28005KT 10SM OVC080 27/07 A3034 RMK AO2
SLP156 T02720072
METAR KFLG 291957Z 19006KT 10SM CLR 28/08 A3033 RMK AO2 SLP148
OCNL LTGCG CB W MOV LTL T02780078
METAR KFLG 292057Z 31008G16KT 280V350 10SM VCTS SCT110 BKN150
27/08 A3031 RMK AO2 SLP144 T02720083 58012
So Flagstaff did report a thunderstorm (VCTS), beginning at 2057Z. Before that though, LTGCG
and a CB was reported at 1957Z. For the 75-minute period from 1915Z-2030Z, here was the lightning
display around Flagstaff:
Here is the same data, with range rings overlaid:
Prior to 2130Z, there were enough lightning strikes, to trigger a VCTS report at KFLG. But that didn't occur.
Even though a CB was reported to the west, and cloud-to-ground lightning was observed; ALDARS/LAWRS
somehow didn't record the event as a VCTS, and take the appropriate SPECI to warn users.
Prescott, Arizona, 29 Jun 2015:
As an aside (not a case), Prescott (KPRC) had this weather on 29 Jun 2015:
SPECI KPRC 292321Z 35018G23KT 10SM TS BKN100 31/11 A3009
RMK AO2 TSB15 OCNL LTGCG TS S MOV S. OCNL LTGCG
DSNT N-NW T03110111
SPECI KPRC 292345Z 02013G24KT 2SM +RA OVC090 23/17 A3011
RMK AO2 WSHFT 2313 RAB36 TSB15E45 OCNL LTGCG TS
S MOV S. OCNL LTGCG DSNT N-NW P0009 T02280172
METAR KPRC 292353Z 15033G53KT 10SM +TSRA BKN090 23/18 A3016
RMK AO2 PK WND 14053/2353 WSHFT 2313 RAB36 TSB15E45B53
SLP136 FRQ LTGCGIC TS OVH VSBY P0028 60028 T02280178
10350 20222 53006
SPECI KPRC 292355Z 15040G57KT 1/4SM +TSRA SQ SCT047 OVC090
21/17 A3018 RMK AO2 PK WND 15057/2354 PRESRR P0012
T02060172
Radar data for the period showed this:
Does that look like the thunderstorms were moving south, away from PRC?
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Post by tornado on Jul 2, 2015 11:46:00 GMT -5
151. Crystal Airport, Minneapolis, Minnesota, 29 Jun 2015:Minneapolis-Crystal Airport (KMIC) reported scattered clouds at 1953Z on 29 Jun. But the next hour, ATC put ASOS into AUTO mode for the 2053Z METAR; ASOS was also in TSNO mode. On page 120 of FAA Order 7900.5C, paragraph 14-58.d. states, METAR KMIC 291953Z 29010KT 9SM SCT075 28/17 A2978 RMK AO2 SLP080 T02780167 METAR KMIC 292053Z AUTO 26009KT 6SM -RA FEW050 SCT095 OVC110 25/18 A2977 RMK AO2 RAB31 SLP076 P0001 60001 T02500178 57013 TSNOMETAR KMIC 292153Z 23006KT 7SM CLR 26/17 A2976 RMK AO2 RAE17 SLP075 P0000 T02560172 So here is what lightning data showed, between 2000Z and 2100Z on 29 Jun:  Below is the same data, with range rings overlaid:  There were 3 lightning bolts that struck within the red 5-mile range ring around KMIC (the 3rd bolt is hard to see, but is to the west, right on Interstate 94). There were also other lightning bolts within the green 10-mile range ring, that met the criteria for reporting VCTS. That's not possible when ATC signs off ASOS and puts it into TSNO mode!As a reminder, here is what the 7900.5C says about service levels, from page 154:
Any time a Service Level C site, logs off ASOS, and puts ASOS into TSNO mode; the ASOS is then operating
at Service Level D. C sites report thunderstorms; D sites are not required to do so, although sometimes they do.
But this was a clear degradation of service, that the FAA has claimed has not occurred!
Lightning data can also ascertain the time of the nearest strike to KMIC:
The time on the above map, is valid for the period 2045-2050Z on 29 Jun. Since the 2 bolts to the west are blue
in color, they likely occurred at 2045Z or 2046Z at the latest. Minutes later, this was the report from this level
C LAWRS site:
METAR KMIC 292053Z AUTO 26009KT 6SM -RA FEW050 SCT095 OVC110
25/18 A2977 RMK AO2 RAB31 SLP076 P0001 60001 T02500178
57013 TSNO
KMIC missed reporting that thunderstorm; by signing off ASOS and putting it into AUTO/TSNO mode, when
they shouldn't have signed off at all. But later, there was another issue.
That was the lightning display for a 90-minute period, valid 29/2330Z-30/0100Z.
Here is the same data, with range rings superimposed:
2 lightning strikes were within the red 5-mile range ring around KMIC. We can narrow down the time of the
nearest lightning strike, to between 2355Z on the 29th, and 0000Z on the 30th:
That lightning bolt, to the NE on Brookdale Drive, was a bit less than 3 miles from KMIC. Since it is orange
in color, we can use the color scale to determine that it stuck about 2358-2359Z. Yet, here was the weather
report from KMIC, minutes earlier:
METAR KMIC 292353Z 30007KT 7SM CLR 28/17 A2977 RMK AO2 SLP076
60001 T02780172 10289 20244 53001
There was no mention of lightning at all in that report. The next METAR reported this:
METAR KMIC 300053Z 15005KT 4SM RA FEW043 BKN049 OVC090 21/17
A2978 RMK AO2 RAB38 SLP080 P0003 T02060172
So there was not only moderate rain in the 2300Z-0100Z time frame; the above lightning maps show that there
was also lightning near KMIC during that time frame- and some of that was within 5 miles. This means Crystal
Airport missed reporting 2 thunderstorms that occurred on June 29th!
152. Lakefront Airport, New Orleans, Louisiana, 29 Jun 2015:
On the 29th of June, New Orleans-Lakefront (KNEW) went from reporting clear skies at 2053Z, to reporting
heavy rain at 2153Z, and beyond:
METAR KNEW 292053Z 02014KT 10SM CLR 32/24 A3001 RMK AO2 SLP155
T03220239 56013
METAR KNEW 292153Z 26018G21KT 2 1/2SM +RA SCT023 BKN037 BKN065
29/23 A3003 RMK AO2 TWR VIS 10 RAB04E13B47 SLP162
P0003 T02890233
SPECI KNEW 292202Z VRB03KT 3SM +RA FEW023 SCT037 BKN060 28/22
A3001 RMK AO2 PRESFR P0005 T02780222
METAR KNEW 292253Z 00000KT 10SM CLR 29/24 A3001 RMK AO2 RAE18
SLP155 P0006 T02940239
The lightning display from 2100Z-2300Z, which was the time surrounding the heavy rain, showed this around KNEW:
Here is the same data, with range rings added:
There was clearly a lot of lightning within the green 10-mile range ring, that met VCTS criteria. There were also 2
bolts of lightning that struck within the red 5-mile range ring, that should have triggered a SPECI for TS. Yet neither
TS nor VCTS was reported. The time of the nearest lightning bolt, can be narrowed down:
The map above is valid for the 5-minute period of 2115-2120Z. Lightning struck just off Interstate 10, to the south of
KNEW, at a range of about 3 miles; with another bolt 4 miles away from the airport. But ALDARS at Lakefront
Airport missed that lightning, plus the other lightning within 10 miles.
153. Gulfport-Biloxi Regional Airport, Mississippi, 29 Jun 2015:
Gulfport (KGPT) had thunderstorms after 1900Z. But in the 2 hours before then, KGPT reported moderate rain
(showers), occasionally with resultant poor visibility:
METAR KGPT 291653Z 29006KT 10SM FEW032 29/22 A3005 RMK AO2
SLP176 T02890222
SPECI KGPT 291738Z VRB03KT 1 1/2SM RA SCT026 BKN031 OVC090
28/23 A3006 RMK AO2 RAB35 P0005 T02830233
SPECI KGPT 291746Z 21012G18KT 1 1/2SM RA SCT020 BKN024 OVC090
27/24 A3006 RMK AO2 VIS 3/4V4 RAB35 P0007 T02670239
SPECI KGPT 291749Z 20011G22KT 170V240 3SM RA BR SCT020 BKN024
OVC070 25/23 A3005 RMK AO2 RAB35 P0007
METAR KGPT 291753Z 18013G22KT 5SM RA SCT020 BKN026 BKN031
24/21 A3005 RMK AO2 RAB35 SLP176 P0007 60007 T02390206
10294 20233 51002
SPECI KGPT 291808Z 17006KT 10SM RA SCT019 BKN100 24/21 A3005
RMK AO2 P0000 T02390211
METAR KGPT 291853Z 30004KT 10SM -RA FEW043 FEW055 BKN110
27/24 A3004 RMK AO2 SLP171 P0000 T02720239
SPECI KGPT 291924Z 36007G17KT 2SM +TSRA BR SCT049 BKN070
OVC090 24/23 A3005 RMK AO2 LTG DSNT ALQDS P0018
T02390228
Note that there was no thunderstorm beginning time on the 1924Z SPECI (nor was there one on the following METAR).
The below map is from Weather Tap. It is a lightning animation that ends at 1900Z. It shows lightning had already
reached the Gulfport area by 1900Z- though certainly more was on the way:
The lightning strike display from 1700Z-1900Z around KGPT was as follows:
Here is the same data, with range rings added:
By the colors of the lightning strikes, it is evident that thunderstorms were moving from southeast
to northwest during that 2 hour period. There were many lightning strikes within the green 10-mile
range ring; that should have triggered ALDARS to generate a SPECI for VCTS. There were also
some 25 lightning bolts that struck within the red 5-mile range ring; ALDARS should have taken a
SPECI to record TS, but did not. So that was an unreported thunderstorm, with more than 2 dozen
lightning bolts that should have warned ground crews that there was a weather hazard. Especially in
light of this:
The above map is valid 1750-1755Z. It is zoomed in on Gulfport-Biloxi Airport, to show that there
were 3 lightning bolts that struck airport property during that 5-minute period; plus 2 other bolts that
struck just outside the airport. Despite all this, KGPT did not report a thunderstorm until 1924Z!
Calculating the lead time, or warning time, we come up with a negative 1 hour and 29 minutes! That
means LTGCG AT AP was occurring, about an hour and a half before a thunderstorm was even reported!
154. St. Lucie County International Airport, Ft. Pierce, Florida, 29 Jun 2015:
Ft. Pierce (KFPR) had heavy rain (showers) and gusty winds, between 1900Z-2000Z on 29 Jun:
METAR KFPR 291853Z 05005KT 10SM BKN049 OVC060 28/21 A3005
RMK AO2 SLP176 T02830211
SPECI KFPR 291909Z 31019G35KT 1 3/4SM +RA FEW020 BKN047 OVC070
23/20 A3010 RMK AO2 PK WND 31035/1907 RAB06 P0004
T02280200
SPECI KFPR 291937Z 30012G20KT 1 3/4SM RA BR FEW007 BKN027
OVC070 22/22 A3012 RMK AO2 PK WND 31035/1907 RAB06
P0027 T02220217
SPECI KFPR 291944Z 29007G18KT 1/2SM +RA FG FEW007 BKN025
OVC070 22/22 A3012 RMK AO2 PK WND 31035/1907 RAB06
P0044 T02220217
SPECI KFPR 291948Z VRB03G18KT 3/4SM RA BR SCT005 BKN030 OVC070
22/22 A3012 RMK AO2 PK WND 31035/1907 RAB06 P0045
METAR KFPR 291953Z 00000KT 1 3/4SM RA BR SCT007 BKN035 OVC090
22/22 A3013 RMK AO2 PK WND 31035/1907 RAB06 SLP201
P0046 T02220222
That seems like it could have been a thunderstorm. Was it? KFPR should have known storms were
approaching from the west. Here is a Weather Tap lightning animation, up to 1900Z:
Lightning strike data between 1900Z-2000Z, was as follows:
Range rings have been added to the chart below, valid for the same hour:
So yes, that was a thunderstorm! ALDARS somehow missed all that lightning within the green 10-mile
range ring, as VCTS was not recorded that hour. Also, ALDARS missed 9 lightning bolts that struck
within the red 5-mile range ring, by not reporting TS. The closest lightning strike was about a mile to the
west of the airport:
The above map is valid from 1940-1945Z. The SPECI that recorded 1/2SM +RA FG was taken at 1944Z;
instead, it should have read 1/2SM +TSRA
That was another thunderstorm with quite a bit of lightning, that somehow ALDARS/LAWRS missed! 155. Flagstaff, Arizona, 29 (30) Jun 2015:On the evening of June 29th, which was the 30th of June UTC, Flagstaff (KFLG) reported a bit of light rain: METAR KFLG 292357Z 28004KT 10SM FEW033 SCT095 27/08 A3028 RMK AO2 SLP145 60040 T02670078 10294 20156 58009 METAR KFLG 300057Z 26004KT 10SM SCT110 26/11 A3028 RMK AO2 SLP147 T02560106 METAR KFLG 300157Z 36009KT 10SM -RA BKN095 OVC120 21/13 A3030 RMK AO2 RAB53 SLP154 P0000 T02060128 METAR KFLG 300257Z 22004KT 10SM -RA SCT033 SCT045 BKN075 17/13 A3033 RMK AO2 PK WND 36033/0215 SLP160 P0001 60001 T01670133 53016 METAR KFLG 300357Z AUTO 28004KT 10SM CLR 16/13 A3034 RMK AO2 RAE03 SLP161 P0000 T01560133 TSNO ATC went home by 0357Z, and put ASOS into AUTO/TSNO mode. But for the 3 hours preceding that time, there had also been a wind gust to 33 knots. Could that have been due to a thunderstorm? The lightning archive between 0000Z and 0300Z shows this:  Here is the same data, with range rings:  The above map clearly shows lots of lightning, both within the green 10-mile range ring; as well as within the red 5-mile range ring. ALDARS, if installed at that site, somehow missed all that lightning. If ALDARS is not installed at KFLG, ATC missed all that lightning. That was despite the meteorological clues: light rain, gusty winds. It was also despite the TAF, which called for thunderstorms during that 3-hour period: TAF AMD KFLG 292230Z 2922/3018 28007KT P6SM VCTS SCT050CB BKN100 TEMPO 2923/3002 VRB10G15KT P6SM -TSRA BKN050CB OVC080 FM300300 VRB05KT P6SM SCT100 BKN120 FM300600 VRB03KT P6SM FEW120 The closest lightning to KFLG struck between 0100Z and 0200Z, which is the time of the following map. Note that there were several lightning bolts that struck nearby:  Those lightning bolts struck generally to the north of KFLG. One clue that there could have been thunderstorms nearby, was the wind gust to 33 knots. When a thunderstorm downburst hits the ground, it tends to spread out in all directions. That enables a keen observer to know where to look for the lightning: the direction from which the strong wind gust had just come; in this case, to the north. KFLG missed reporting any thunderstorm or lightning activity during the last 3 hours
on duty that evening. Attachments:
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