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A METAR is a routine aviation weather observation for one airport. A TAF is the forecast for the same airport over the next 24 to 30 hours. Both use a compact code that looks cryptic at first, but they follow a fixed order. Once you know the order, you can read most reports in a few seconds.
You can fetch the latest reports for any airport with our METAR & TAF Weather tool, which also decodes them. This guide explains what each part means so you can check the decode yourself.
A real METAR, decoded
Here is a typical summer report from Dubai International (OMDB):
METAR OMDB 010830Z 16007KT 110V220 CAVOK 40/16 Q1009 BECMG 33012KT
| Group | Meaning |
|---|---|
METAR | Report type. SPECI means a special report issued because conditions changed significantly. |
OMDB | ICAO airport code. Use our Airport Code Lookup if you only know the IATA code (DXB). |
010830Z | Day of the month (01) and time (08:30) in UTC. The Z stands for Zulu, aviation shorthand for UTC. |
16007KT | Wind from 160° at 7 knots. Wind direction in a METAR is measured from true north. |
110V220 | Wind direction varying between 110° and 220°. |
CAVOK | Ceiling and visibility OK: visibility 10 km or more, no cloud below 5,000 ft (or the highest minimum sector altitude, if higher), no cumulonimbus or towering cumulus, and no significant weather. |
40/16 | Temperature 40 °C, dew point 16 °C. An M prefix means minus, for example M02. |
Q1009 | QNH 1009 hPa. US reports use A and inches of mercury, for example A2992. |
BECMG 33012KT | Trend: the wind is expected to become 330° at 12 knots within the next two hours. |
The groups you will meet most often
Wind
Wind is shown as direction (three digits) and speed, for example 27015G25KT: 270° at 15 knots, gusting 25. VRB03KT means light and variable. 00000KT means calm. Some countries report speed in metres per second (MPS); 1 m/s is about 1.94 knots.
Visibility
Outside North America, visibility is in metres: 4000 means 4,000 m, and 9999 means 10 km or more. US and Canadian reports use statute miles, for example 10SM. A runway visual range group such as R12L/0600 gives the RVR for runway 12L in metres.
Weather
Present weather uses two-letter codes with an intensity prefix: - light, no sign moderate, + heavy. Common codes include RA rain, SH showers, TS thunderstorm, BR mist, FG fog, HZ haze, DU widespread dust and SA sand. In the Gulf, HZ and DU are frequent and can drop visibility sharply. VC means in the vicinity, not at the airport itself.
Cloud
Cloud groups show coverage in eighths of the sky (oktas) and base height in hundreds of feet above the aerodrome:
FEW1–2 oktas,SCT3–4,BKN5–7,OVC8.BKN015means broken cloud with a base of 1,500 ft.CBorTCUafter a group, for exampleSCT030CB, flags cumulonimbus or towering cumulus.NSCmeans no significant cloud andVV002means the sky is obscured with vertical visibility of 200 ft.
The ceiling is the lowest BKN or OVC layer. That is the number that matters for most approach minima.
Reading a TAF
A TAF uses the same building blocks plus time periods and change groups. For example:
TAF OMDB 010500Z 0106/0212 34010KT CAVOK BECMG 0110/0112 34015KT TEMPO 0200/0204 4000 HZ
010500Zis the issue time.0106/0212is the validity: from the 1st at 06Z to the 2nd at 12Z.- The first block is the base forecast: wind 340° at 10 knots, CAVOK.
BECMG 0110/0112: a permanent change happening between 10Z and 12Z on the 1st.TEMPO 0200/0204 4000 HZ: temporary fluctuations, each lasting less than an hour, during that window. Here, visibility drops to 4,000 m in haze.FM011500(from 15:00Z on the 1st) introduces a complete new set of conditions.PROB30orPROB40gives a 30% or 40% probability.
Why check both the METAR and the TAF
A METAR tells you what the weather was at the observation time; the TAF tells you what is expected over the coming hours. Neither is enough on its own. A METAR showing CAVOK can sit alongside a TAF forecasting haze and 4,000 m visibility by your arrival time, and poor current conditions may be forecast to improve. Read the latest METAR for what is happening now, then the TAF for your departure and arrival windows, and pay attention wherever the two disagree.
Common mistakes
- Forgetting the time is UTC. Dubai is UTC+4, so 0830Z is 12:30 local. Our UTC / Local Time converter handles the date change after midnight.
- Using METAR wind directly against a magnetic runway heading. METAR wind is true. ATIS and tower winds are magnetic. Where magnetic variation is large, the difference matters for crosswind calculations.
- Reading an old report. Most airports issue METARs every 30 or 60 minutes. Always check the timestamp.
- Treating TEMPO as unimportant. For planning, many operators must consider the worse TEMPO conditions within the period.
Next steps
Practise by pulling reports for airports you know in the METAR & TAF tool and decoding them yourself before you read the decoded version. When you have the wind, run it through the Crosswind & Headwind Calculator for your runway.
This guide is for education. For flight planning, use your official briefing service, current publications and your operator’s procedures.
FAQ
How often is a METAR issued?
Most stations issue a routine METAR every hour; many large airports issue them every 30 minutes. When conditions change significantly between routine reports, a SPECI (special report) is issued.
What is the difference between METAR and TAF wind directions and ATIS?
Winds in METARs and TAFs are given in degrees true. Winds broadcast by ATIS and given by the tower are in degrees magnetic, so they can line up directly with runway headings.
Is visibility in metres or statute miles?
Both are used. Most countries report visibility in metres (9999 means 10 km or more). The United States and Canada report statute miles (10SM). Look for the SM suffix.
Why does my TAF say AMD or COR?
AMD marks an amended forecast issued because the previous one no longer describes the expected weather. COR marks a corrected report or forecast. Always use the latest version.
Sources and further reading
- AviationWeather.gov (NWS Aviation Weather Center) (official US source of METAR and TAF data used by the USFITools decoder)
- AIM 7-1, Meteorology
- FAA Aviation Handbooks and Manuals (includes the Aviation Weather Handbook, FAA-H-8083-28)
- ICAO Annex 3, Meteorological Service for International Air Navigation (METAR and TAF code formats)
Sources checked November 2026. Rules differ between countries and change over time: for real flights, use the current publications of the authority that applies to you, your aircraft flight manual and your operator’s procedures.