How to Read and Decode METAR Weather Reports

The report begins with the four-letter ICAO station identifier (e.g., KJFK), followed by the date and time of observation in UTC (e.g., 281400Z). Modifiers like AUTO indicate automated sensor generation, while COR signifies a corrected bulletin.

The wind group provides true direction in three digits and speed in knots (e.g., 14012G22KT for 140° at 12 knots gusting to 22 knots). Variable winds are denoted by VRB or directional range brackets such as 090V160.

Horizontal visibility is reported in statute miles (US) or meters (ICAO). 9999 represents 10 km or greater. Runway Visual Range (RVR) follows the format R10/1200N for runway 10 with 1,200 meters visual range.

Weather phenomena combine intensity qualifiers (+ heavy, - light), descriptors (TS thunderstorm, SH shower, FZ freezing), and precipitation types (RA rain, DZ drizzle, SN snow, FG fog, BR mist, HZ haze).

Cloud amount is categorized in oktas: FEW (1-2), SCT (3-4), BKN (5-7), and OVC (8), followed by base height in hundreds of feet AGL (e.g., BKN025 = ceiling at 2,500 ft). Convective clouds carry CB (Cumulonimbus) or TCU (Towering Cumulus) suffixes.

Temperature and dew point appear as 24/18 (24°C temperature, 18°C dew point; sub-zero values prefix M). Altimeter setting is reported as A2992 (inches of mercury) or Q1016 (hectopascals).