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How to read a METAR and a TAF
The weather report codes that show up in Part 107 questions, decoded in order. Every line comes from the FAA Aviation Weather Handbook (FAA-H-8083-28B); the section number is given so you can check it.
A METAR, piece by piece
Example from the handbook's own codes: METAR KSEA 011955Z AUTO 22015G25KT 1/2SM +SHRA BKN008 OVC015 04/M02 A2992 RMK AO2
| Code | Meaning | Handbook |
|---|---|---|
METAR / SPECI | Routine report, made near the top of each hour / unscheduled special report taken between hourly reports. | 24.4.1, 24.4.2 |
KSEA | Four-letter ICAO station code; in the contiguous US it is K plus the three-letter airport code (SEA becomes KSEA). | 24.4.3.2 |
011955Z | Day of the month (01), then hour and minutes (1955); Z means UTC. | 24.4.3.3 |
AUTO / COR | Fully automated report with no human oversight / a corrected report. | 24.4.3.4 |
22015G25KT | Wind from 220 degrees true at 15 knots, gusting to 25 knots. Direction is in tens of degrees from true north. | 24.4.3.5 |
VRB03KT, 21010KT 180V240, 00000KT | Variable direction at 6 knots or less; direction varying from 180 to 240 degrees; calm. | 24.4.3.5 |
1/2SM, M1/4SM | Visibility in statute miles; M means "less than" at US automated stations. | 24.4.3.6 |
R01L/0800FT | Runway visual range: runway 01L, 800 feet. | 24.4.3.7 |
+SHRA, -DZ, VCTS | Present weather: + heavy, - light, no sign moderate. SH shower, RA rain, DZ drizzle, SN snow, TS thunderstorm, FZ freezing, BR mist, FG fog, HZ haze. VC means 5 to 10 statute miles from the station. | 24.4.3.8 |
BKN008 OVC015 | Sky cover with height in hundreds of feet above the ground: FEW 1-2 eighths, SCT 3-4, BKN 5-7, OVC 8 eighths. CLR (automated) means no clouds at or below 12,000 feet. | 24.4.3.9 |
VV001 | Indefinite ceiling: vertical visibility 100 feet above the ground. | 24.4.3.9 |
| Ceiling | The lowest broken or overcast layer; if the sky is totally obscured, the vertical visibility. In the example: 800 feet. | 24.4.3.9 |
04/M02 | Temperature 4 °C, dew point minus 2 °C (M means below zero). | 24.4.3.10 |
A2992 | Altimeter setting 29.92 inches of mercury. | 24.4.3.11 |
RMK AO2 | Remarks follow RMK. AO2: automated station with a precipitation discriminator (AO1: without). | 24.4.3.12, 24.4.3.13 |
A TAF, the parts that differ
| Code | Meaning | Handbook |
|---|---|---|
1512/1612 | Valid period: from the 15th at 1200 UTC to the 16th at 1200 UTC. Most TAFs cover 24 hours; some major airports 30 hours. | 27.4.1, 27.4.2.4 |
| Issue times | Scheduled TAFs are issued four times a day, at 0000, 0600, 1200 and 1800Z, and cover the area within 5 statute miles of the runway complex. | 27.4, 27.4.2.4 |
P6SM | Visibility greater than 6 statute miles (a TAF code). | 27.4.2.6 |
FM151800 | "From": conditions change significantly at that day and time (15th, 1800 UTC); everything before it is replaced. | 27.4.2.10.1 |
TEMPO | Temporary fluctuations: more than 50 percent likely, each lasting an hour or less, together under half the period. | 27.4.2.10.2 |
PROB30 | A 30 percent chance of a thunderstorm or precipitation event. | 27.4.2.10.3 |
WS020/27055KT | Low-level wind shear up to 2,000 feet above the ground, with wind from 270 degrees at 55 knots at that height (not an amount of shear). | 27.4.2.9.4 |
Source: FAA Aviation Weather Handbook, FAA-H-8083-28B, Chapters 24 (METAR) and 27 (TAF). The example METAR combines the handbook's own example codes into one line for practice; it is not a real observation.
These questions are original and written from public FAA documents. Chartpass is not affiliated with, endorsed by, or sponsored by the FAA. Chart excerpts are FAA public domain material and are not for navigation.