How to Read a METAR & TAF
A METAR is a station observation; a TAF is a forecast for a stated period. Read the station and UTC times first, then decode the weather groups.
Start with the station and time
A report such as METAR KMCO 101553Z identifies KMCO and an observation on the 10th day of the month at 15:53 UTC. TAFs also include an issue time and a valid period. When comparing reports, check the time before comparing the weather itself; a perfectly decoded report can still be too old to describe what is happening now.
Wind
A wind group such as 19010G18KT means wind from 190 degrees true at 10 knots with gusts to 18 knots. VRB06KT means direction variable at 6 knots. 00000KT means calm, not a north wind. Gust speed is the peak reported speed, not an amount to add to the sustained speed. Some reports add a variable-direction group such as 160V230. Surface wind is airport context and should not be substituted for an enroute wind forecast.
Visibility
In U.S. METARs, prevailing visibility is commonly shown in statute miles. A group such as 10SM means 10 statute miles. Lower values can be written as whole numbers, fractions, or mixed numbers. Runway visual range may appear in a separate RVR group when applicable.
Weather phenomena
Weather groups combine intensity, descriptors, and phenomena. RA means rain, SN snow, BR mist, FG fog, TS thunderstorm, SH showers, and FZ freezing. A minus sign means light and a plus sign means heavy for applicable phenomena. Because several codes can be combined, always keep the original group visible while interpreting it.
Clouds and ceilings
Cloud groups use FEW, SCT, BKN, OVC, or VV followed by height in hundreds of feet AGL. BKN020 means broken clouds at 2,000 feet AGL. In aviation weather reporting, broken and overcast layers and vertical visibility can establish a ceiling; few and scattered layers do not by themselves.
Temperature and dew point
A group such as 22/12 means temperature 22°C and dew point 12°C. A leading M indicates a negative value. The temperature/dew-point spread can help you think about moisture and possible visibility or cloud concerns, but it is only one part of the weather picture.
Putting the groups together
This constructed example shows METAR group order; it is not a live observation: METAR KDEN 231653Z 32018G28KT 10SM -RA SCT015 BKN025 18/14 A2992. Read it as a report for KDEN on day 23 at 16:53 UTC; wind from 320° at 18 kt gusting 28; 10 statute miles visibility; light rain; scattered clouds at 1,500 ft AGL; broken clouds at 2,500 ft AGL; temperature 18°C and dew point 14°C; altimeter 29.92 inHg. The broken layer makes the reported ceiling 2,500 ft AGL. The gusts and ceiling deserve attention, but one station report does not describe conditions along a route or guarantee the runway-specific wind.
Altimeter setting
In a U.S. METAR, A2989 means an altimeter setting of 29.89 inHg. Other regions may use a QNH group such as Q1013, expressed in hectopascals. Keep the coded value and units attached when reading or copying it.
TAF base conditions and change groups
A TAF begins with forecast conditions that apply until a change group modifies them. FM introduces conditions expected from a specific time forward. TEMPO identifies temporary fluctuations during a stated period. Other permitted groups can describe gradual changes or probabilities depending on the issuing format and region. The safest habit is to read the TAF as a timeline rather than as one long sentence.
Read a TAF as a time sequence
For example, in a constructed fragment FM232000 31012KT P6SM SCT035, FM232000 starts a new forecast period at 20:00 UTC on the 23rd; wind is from 310° at 12 kt, visibility is greater than 6 statute miles, and scattered clouds are at 3,500 ft AGL. A TEMPO group gives temporary fluctuations during its stated window; do not read it as a permanent replacement for the prevailing forecast. Check the TAF issue/valid times and every change group against your planned arrival and alternate times.
Reading TEMPO and FM periods in UTC
This constructed fragment is for practice, not a current forecast: 2318/2418 22010KT P6SM SCT030 TEMPO 2320/2323 3SM SHRA BKN015 FM240000 28012KT P6SM SCT040.
| Time | Interpretation |
|---|---|
| 23rd, 18:00 onward | Base: wind 220° at 10 kt, visibility over 6 SM, scattered 3,000 ft. |
| 23rd, 20:00–23:00 | Temporary: 3 SM, rain showers, broken 1,500 ft. The base still applies between temporary fluctuations. |
| 24th, 00:00 onward | New prevailing conditions: wind 280° at 12 kt, visibility over 6 SM, scattered 4,000 ft. |
At 22:00 on the 23rd, consider both the prevailing forecast and TEMPO. At 00:30 on the 24th, read the new FM period. The forecast crosses midnight; matching only the hour gives the wrong answer.
PROB30 expresses a 30% probability where authorized; international formats can also use PROB40 and BECMG. BECMG describes a transition over an interval. Consult the issuing authority's conventions. See AWC's coded weather reference.
Compare the METAR to the TAF
Once you understand each report, compare the current observation with what the TAF expected. If the METAR is already worse than forecast, or weather is changing faster than the TAF timing implies, that is a reason to widen your weather review rather than simply trusting the forecast line you first noticed.
Use PilotDesk to practice
The PilotDesk METAR Decoder keeps each coded group beside a plain-language explanation. The live weather page adds report freshness, nearby reporting stations, runway-wind context, and separated raw TAF change groups. The Airport Search ties those weather tools to procedures and route planning.
Official references
For current data and authoritative weather guidance, use the Aviation Weather Center and FAA aviation weather publications, including the FAA Aeronautical Information Manual weather services chapter. Examples on this page are instructional constructions, not current weather. PilotDesk keeps links to the official sources beside the simplified explanation.