METAR decoding in Europe

Basic Met Reports

TAF - Aerodrome Forecast

An aerodrome
TAF is a forecast - it will give the predicted weather conditions expected at an aerodrome, usually for a 9 or 24 hour period. The standard 9 hour TAF is updated and reissued every three hours.

METAR - Aerodrome Actual Met Report

The METAR is a report giving the actual weather conditions at an aerodrome at the time of the report. METAR's are issued every 30 minutes during the opening hours of the aerodrome.
The codes used in both TAF and METAR however are broadly similar and it should not be difficult to decode a TAF if you are happy with the format of a METAR signal.

METAR Decode

A European METAR signal may comprise up to 10 components - preceded by a 3 component identifier.

Identifier Components

  1. Report Type - METAR
  2. Location Indicator - ICAO four letter aerodrome code.
  3. Time - The time of the observation in UTC (GMT) in hours and minutes followed by the letter Z (the universal indication that GMT time is being reported).
Let us look at a typical example or check out our example page:
METAR EHAM 1050Z 24015KT 9000 RA SCT025 BKN040 10/09 Q1010 NOSIG
Note here that not all the 10 weather components are shown. If no data is recorded at the time of observation then certain fields (RVR, weather, wind shear) may be omitted altogether. In addition the cloud component may be used more than once if several cloud layers are present.
I'll continue with a more detailed description of each field and we shall come back to the METAR for EHAM (Amsterdam) at the end.