They are very reliable because they correspond to precise observations. They are composed of estimations on visibility, haziness or measurements of pressure, wind…. The METAR recorded every hour or every 1/2 hour. It is necessary to know the vocabulary of these messages perfectly.

For example: CAVOK for Ceiling and Visibility OK, TS: thunderstom, FG: fog, RA: rain, SN: snow, DZ: drizzle, SH: shower, NOSIG: nothing special, TEMPO: temporarily

We have messages such as:

LFBS 02010 CAVOK 03/MOO 1020 =

LFLN 32008 1200 R0300 40 BCFG 8 ST 006 06/06 TEMPO 0600 =

LFRN 22002 8000 20REDZ 3SC013 3SC030 7SC036 06/04 1017 NOSIG