Aviation weather explained
Pilots and controllers use a completely different weather vocabulary from the general public. Once you know the alphabet soup, aviation reports are the densest weather intel available anywhere.
METAR — the surface observation
A METAR is an hourly airport weather observation. It looks intimidating but has a rigid structure.
Example: KOKC 231553Z 18015G22KT 10SM FEW250 27/17 A2998 RMK AO2
- KOKC — Oklahoma City airport identifier
- 231553Z — day 23, time 15:53 UTC (Zulu)
- 18015G22KT — wind from 180° at 15 knots, gusting 22
- 10SM — visibility 10 statute miles
- FEW250 — few clouds at 25,000 ft
- 27/17 — temperature 27°C, dew point 17°C
- A2998 — altimeter 29.98 inches Hg
- RMK AO2 — remarks; AO2 means automated station with precipitation sensor
TAF — the terminal forecast
A TAF is a 24-30 hour forecast for an airport. Same format as METAR but with forecast segments.
Look for keywords: FM (from) starts a new segment, TEMPO means temporary conditions, PROB30 means 30% probability, BECMG means gradually becoming.
PIREP — pilot report
A PIREP is what a pilot reports back from the air. Turbulence, icing, mountain wave, cloud tops. PIREPs are what fill in the gaps between airport surface observations.
Prefix "UUA" = urgent (severe turbulence, severe icing). Prefix "UA" = routine.
SIGMET and AIRMET
The tools
- aviationweather.gov — official NOAA/NWS aviation weather site
- 1800WXBRIEF.com — official flight briefing
- ForeFlight ($99+/yr) — the standard pilot app
- Windy Aviation layer — non-official but excellent visualization