METAR = routine aviation weather report
Report type
Station identifier
Date and time in UTC
Wind direction and speed
Visibility
Runway visual range, if reported
Weather phenomena
Sky condition / cloud layers
Temperature and dew point
Altimeter setting
Remarks, if included
Example format: METAR KJFK 121651Z 18012KT 10SM FEW020 SCT050 25/17 A2992 RMK AO2
METAR
KJFK = station
121651Z = day 12, time 1651 UTC
18012KT = wind from 180 degrees at 12 knots
10SM = visibility 10 statute miles
FEW020 = few clouds at 2,000 feet
SCT050 = scattered clouds at 5,000 feet
25/17 = temperature 25°C, dew point 17°C
A2992 = altimeter 29.92 inHg
RMK AO2 = remarks section, automated station with precipitation sensor
Wind groups may include gusts, variable direction, or calm
Visibility may be in statute miles or meters depending on country
Weather codes may include rain, snow, fog, thunderstorm, mist, drizzle, hail
Cloud amounts may include SKC, CLR, FEW, SCT, BKN, OVC
Cloud heights are usually in hundreds of feet above ground level
CAVOK means ceiling and visibility OK
QNH may appear as Q#### in hectopascals outside the U.S.
NOSIG means no significant change expected
TEMPO means temporary conditions
BECMG means conditions becoming
PROB means probability of occurrence