How to Read a METAR
A complete guide to decoding METAR aviation weather reports, with real-world examples.
What is a METAR?
A METAR (Meteorological Terminal Air Report) is a standardized format for reporting current weather conditions at an airport. Issued every hour — and more frequently when conditions change rapidly — METARs are the primary source of current weather information for pilots.
METARs are used worldwide and follow a consistent format defined by the International Civil Aviation Organization (ICAO), making them readable by any trained pilot regardless of country.
Example METAR
METAR for San Francisco International Airport (KSFO)
Breaking Down Each Element
Station Identifier
The 4-letter ICAO airport code. In the US, codes begin with K (e.g., KSFO = San Francisco). Canadian airports begin with C, European airports with E or L, etc.
Date and Time (Zulu/UTC)
Format: DDHHMMZ. The first two digits are the day of the month (04), followed by the time in UTC (1856Z = 18:56 UTC). The Z indicates Zulu (UTC) time.
Wind
Format: DDDSSKT (direction, speed, knots). Wind from 270° (due west) at 15 knots.
- VRB = variable wind direction
- G = gusts (e.g., 27015G25KT = gusting to 25 kt)
- 00000KT = calm winds
Visibility
Prevailing visibility in statute miles (SM) in the US, or meters internationally. 10SM = 10 statute miles (maximum reported in the US).
- M1/4SM = less than 1/4 mile
- 9999 = 10 km or more (international format)
Sky Conditions
Cloud coverage and height in hundreds of feet AGL. Multiple layers may be reported.
FEW020 = Few clouds at 2,000 ft AGL. BKN120 = Broken layer at 12,000 ft AGL.
Temperature / Dew Point
Temperature and dew point in degrees Celsius, separated by a slash. 15/08 = temperature 15°C, dew point 8°C. Negative values are prefixed with M (e.g., M05 = −5°C). When temperature and dew point are close, expect fog or low visibility.
Altimeter Setting
The altimeter setting in inches of mercury (inHg) in the US, prefixed with A. A2992 = 29.92 inHg. International format uses Q followed by hectopascals (e.g., Q1013). Always set your altimeter to the current local setting before landing.
Remarks (RMK)
Additional information follows the RMK token.
- AO1 = automated station without precipitation discriminator
- AO2 = automated station with precipitation discriminator
- SLP132 = sea level pressure 1013.2 hPa
Frequently Asked Questions
What does METAR stand for?
METAR stands for Meteorological Terminal Air Report (from the French "Météorologique Aviation Régulière"). It is the standard format for reporting current weather conditions at airports.
How often are METARs issued?
METARs are issued every hour (routine METAR) and as special reports (SPECI) when significant weather changes occur, such as rapidly changing visibility, wind shifts, or the onset of precipitation.
What is the difference between METAR and SPECI?
A METAR is a routine hourly weather observation. A SPECI is a special observation issued between routine reports when conditions change significantly — for example, when visibility drops below certain thresholds or wind shifts rapidly.