Need Authoritative METAR Specifications

[grumpyoldgeek]

Can anyone post a link to the authoritative definitions of the METAR data fields, either by AIM circular or ICAO document?

[bsal]

Here's a great one just click on the link FMH-1 (http://www.ofcm.gov/fmh-1/fmh1.htm)

[bobrun]

Have a look in a AERAD flight guide book, it`s all described in it. Sorry, don't have a link for it.

[Henry VIII]

ICAO Annex 3 (http://dcaa.slv.dk:8000/icaodocs/Annex%20III%20-%20Meteorological%20Service%20for%20International%20Air%20Na vigation/Cover%20sheet%20to%20AMDT%2074.pdf)