How to Read a METAR

A METAR looks intimidating the first time you see it — a dense string of letters and numbers with no spaces to spare. But every METAR follows the same fixed order, so once you learn the sequence you can decode any report in the world. This guide walks through each field in the order it appears, decodes two complete reports, and points out the mistakes that trip up new pilots.

What a METAR is (and is not)

METAR stands for Meteorological Aerodrome Report. It is an observation of surface weather at an airport, usually taken once an hour near 55 minutes past the hour. It is not a forecast — that is the job of the TAF. A METAR tells you what the weather is doing right now at one specific point on the field, and nothing more. When conditions change sharply between hourly observations, the station issues a special report called a SPECI, which uses the exact same format.

The fixed order of a METAR

Reading left to right, a METAR always presents its fields in this sequence:

1. Report type (METAR or SPECI)
2. Station identifier (4-letter ICAO code)
3. Date and time of observation (in UTC / Zulu)
4. Modifier (AUTO or COR), if present
5. Wind
6. Visibility
7. Runway visual range (RVR), if reported
8. Present weather
9. Sky condition (cloud layers)
10. Temperature and dew point
11. Altimeter setting
12. Remarks (everything after RMK)

Not every field appears in every report — if there is no present weather, that group is simply omitted — but the order never changes. That predictability is what makes decoding possible.

Field by field

1. Report type

METAR marks a routine hourly observation; SPECI marks a special observation triggered by a significant change. In the United States the leading METAR label is often dropped from the raw text.

2. Station identifier

A four-letter ICAO code identifies the reporting station, for example KJFK (New York's Kennedy), KORD (Chicago O'Hare), or EGLL (London Heathrow). In the contiguous United States the code is the letter K followed by the familiar three-letter identifier.

3. Date and time

The time group is six digits followed by Z: two digits for the day of the month, four for the time, always in UTC (Zulu). 151751Z means the 15th day at 17:51 UTC. Aviation weather uses UTC everywhere so that a report is unambiguous regardless of local time zone.

4. Modifier

AUTO means the observation came from an automated station with no human augmentation. COR means the report is a correction to a previously transmitted one.

5. Wind

Wind is encoded as direction, speed, and unit — 18012KT is wind from 180° (true, not magnetic) at 12 knots. A G marks gusts: 18012G22KT is 12 knots gusting 22. Direction VRB means variable (typical of light and shifting winds), and 00000KT is calm. A group such as 150V210 after the wind reports that the direction varied between 150° and 210°.

6. Visibility

In U.S. reports visibility is in statute miles followed by SM: 10SM is ten miles, 1/2SM is half a mile, and P6SM means greater than six miles (the "P" is "plus"). Most of the world reports visibility in meters instead — 9999 means 10 km or more, while 0800 is 800 meters.

7. Runway visual range

When visibility is low, an R group reports the measured range down a specific runway, for example R04R/2400FT — runway 04 Right, 2,400 feet. RVR is decisive for whether an instrument approach is legal.

8. Present weather

Present weather combines an intensity sign, an optional descriptor, and a phenomenon: -RA is light rain, +TSRA is a heavy thunderstorm with rain, BR is mist, and FG is fog. There are dozens of combinations; the full list is covered in METAR Weather Codes.

9. Sky condition

Cloud layers are reported as a coverage abbreviation plus a height in hundreds of feet above ground level: FEW025 (few at 2,500 ft), SCT040 (scattered at 4,000 ft), BKN080 (broken at 8,000 ft), OVC120 (overcast at 12,000 ft). CLR or SKC means clear. The lowest broken or overcast layer is the ceiling — explained in Cloud & Ceiling Codes.

10. Temperature and dew point

Reported in whole degrees Celsius, separated by a slash: 22/14 is 22°C with a 14°C dew point. A leading M means minus — M03/M07 is −3°C over −7°C. The closer the two numbers, the higher the humidity and the greater the chance of fog or low cloud.

11. Altimeter setting

In the United States the altimeter is an A followed by four digits representing inches of mercury: A2998 is 29.98 inHg. Elsewhere it is a Q group in hectopascals, such as Q1013.

12. Remarks

Everything after RMK is supplementary: automated-station type, sea-level pressure, precise temperatures, peak winds, and more. Remarks have their own dedicated guide, METAR Remarks (RMK).

Worked example 1

METAR KJFK 151751Z 18012G22KT 10SM FEW025 BKN080 22/14 A2998 RMK AO2 SLP152

Bottom line: a pleasant afternoon at JFK with an 8,000-foot ceiling and ten miles of visibility — comfortably VFR.

Worked example 2 (low IFR)

METAR KSFO 120956Z 21006KT 1/4SM R28R/1600V2200FT FG VV002 12/12 A2991 RMK AO2

With a 200-foot vertical visibility and a quarter mile in fog, this is Low IFR. Note the temperature and dew point are equal, the classic signature of fog. Read more in Aviation Flight Categories.

Common mistakes

• Reading the time as local. It is always UTC — convert it yourself.
• Treating FEW or SCT as a ceiling. Only BKN, OVC, and VV establish a ceiling.
• Confusing true and magnetic wind when computing crosswinds.
• Assuming P6SM is exactly six miles — it means more than six.
• Ignoring the remarks, where the precise pressure and temperature often live.

Limitations

A METAR describes one point on the airport at one moment. Conditions a few miles away, or a few minutes later, can differ — especially around fog, convection, and terrain. Automated stations also have blind spots: they may not classify certain precipitation types or detect distant thunderstorms. A METAR is one input to a decision, never the whole picture.

Official sources

• FAA Aviation Weather Handbook (FAA-H-8083-28) and Advisory Circular AC 00-45 — the authoritative U.S. references for weather report formats.
• NWS Aviation Weather Center — aviationweather.gov — live METAR and TAF data.
• Leidos Flight Service — 1800wxbrief.com — official preflight briefings.