Post by tornado on Feb 28, 2018 12:31:16 GMT -5
From FAA Order 7900.5D:
Some AO2 sites still don't report rain in present weather:
Grand Prairie, Texas, 23 Feb 2018:
METAR KGPM 230955Z AUTO 00000KT 4SM SCT003 BKN009 OVC013
04/04 A3024 RMK AO2 P0015 T00380038
METAR KGPM 230935Z AUTO 00000KT 4SM BKN003 BKN007 OVC012
04/04 A3024 RMK AO2 P0012 T00400040
METAR KGPM 230915Z AUTO 27003KT 3SM SCT005 BKN008 OVC013
04/04 A3024 RMK AO2 P0006 T00390039
METAR KGPM 230855Z AUTO 00000KT 3SM BKN005 OVC011 04/04 A3024
RMK AO2 P0025 60026 T00400040
METAR KGPM 230835Z AUTO 00000KT 2 1/2SM BKN007 OVC010 04/04
A3023 RMK AO2 P0020 T00400040
METAR KGPM 230815Z AUTO 00000KT 2SM OVC007 04/04 A3024 RMK
AO2 P0014 T00400040
METAR KGPM 230755Z AUTO 00000KT 5SM OVC007 04/04 A3025 RMK
AO2 T00420042
Users were not informed of a present weather type. Savvy users could discern that it
was raining, based on the .25" hourly accumulation at 0855Z, and the .15" hourly
accumulation at 0955Z. What else was missing from those reports? LTG & TS:
AO2: it's no guarantee of a complete weather report!
2.8.c. Table 2-1 summarizes the weather elements that are available at automated observing systems with precipitation discrimination capability (AO2) and those without precipitation discrimination capability (AO1).
14.22. Type of Automated Station (AO1 or AO2). AO1 or AO2 is coded in all METAR/SPECI from automated stations. Automated stations without a precipitation discriminator are identified as AO1; automated stations with a precipitation discriminator are identified as AO2.
Table 2-1 Note 4 Automated stations report only a limited set of present weather and obstruction to vision elements.
Some AO2 sites still don't report rain in present weather:
Grand Prairie, Texas, 23 Feb 2018:
METAR KGPM 230955Z AUTO 00000KT 4SM SCT003 BKN009 OVC013
04/04 A3024 RMK AO2 P0015 T00380038
METAR KGPM 230935Z AUTO 00000KT 4SM BKN003 BKN007 OVC012
04/04 A3024 RMK AO2 P0012 T00400040
METAR KGPM 230915Z AUTO 27003KT 3SM SCT005 BKN008 OVC013
04/04 A3024 RMK AO2 P0006 T00390039
METAR KGPM 230855Z AUTO 00000KT 3SM BKN005 OVC011 04/04 A3024
RMK AO2 P0025 60026 T00400040
METAR KGPM 230835Z AUTO 00000KT 2 1/2SM BKN007 OVC010 04/04
A3023 RMK AO2 P0020 T00400040
METAR KGPM 230815Z AUTO 00000KT 2SM OVC007 04/04 A3024 RMK
AO2 P0014 T00400040
METAR KGPM 230755Z AUTO 00000KT 5SM OVC007 04/04 A3025 RMK
AO2 T00420042
Users were not informed of a present weather type. Savvy users could discern that it
was raining, based on the .25" hourly accumulation at 0855Z, and the .15" hourly
accumulation at 0955Z. What else was missing from those reports? LTG & TS:
AO2: it's no guarantee of a complete weather report!