METAR
METAR (Meteorological Aerodrome Report) is the standard format for reporting current weather conditions at airports.
How to read it?
1. Airport Identifier: Starts with the 4-letter ICAO code of the airport.
2. Time: Always in UTC (Z). Usually updated every 30 minutes, or more often during rapid weather changes.
3. Wind: Measured in knots (KT) or M/S.
- G: Indicates gusts (e.g., G25KT).
- dddVddd: Indicates variable wind direction (e.g., 180V240).
4. Visibility:
- USA: Reported in Statute Miles (SM). Fractions like 1/4 or 1/2 are common.
- International: Reported in meters (m). 9999 means 10 km or more.
4.1 RVR (Runway Visual Range):
The distance a pilot can see down the runway. Format: R[Runway]/[Value] (e.g., R27/1200M).
RVR is reported in METAR when visibility is below 2000 meters.5. Present Weather (Phenomena): Describes significant weather occurring at the airport.
5.1 Qualifiers & Descriptors
| Abbreviation | Description |
|---|---|
| + / - | Heavy / Light intensity |
| VC | In the vicinity (within 8 km/5 SM) |
| TS / SH / FZ | Thunderstorm / Showers / Freezing |
| BL / DR / BC | Blowing / Drifting / Patches |
5.2 Precipitation
| Abbreviation | Description |
|---|---|
| RA / DZ | Rain / Drizzle |
| SN / SG | Snow / Snow Grains |
| GR / GS | Hail / Small Hail |
| IC / PL | Ice Crystals / Ice Pellets |
5.3 Obscurations & Other
| Abbreviation | Description |
|---|---|
| FG / BR / HZ | Fog (Vis < 1 km) / Mist (Vis 1-5 km) / Haze |
| FU / DU / VA | Smoke / Dust / Volcanic Ash |
| SQ / FC | Squall / Funnel Cloud (Tornado/Waterspout) |
6. Clouds: Reported in hundreds of feet. The coverage type is indicated by a three-letter code (detailed in the table below).
| Abbreviation | Description |
|---|---|
| SKC / CLR | Sky Clear / Clear |
| FEW | Few (1/8 to 2/8 coverage) |
| SCT | Scattered (3/8 to 4/8 coverage) |
| BKN | Broken (5/8 to 7/8 coverage) |
| OVC | Overcast (8/8 coverage) |
| CB | Cumulonimbus (Thunderstorm clouds) |
| TCU | Towering Cumulus |
6.2 Vertical Visibility (VV): Reported when the sky is completely obscured.
- Indefinite Ceiling: Used when surface phenomena (fog, smoke, dust) prevent seeing a cloud base.
- Measurement: Reported in hundreds of feet following the VV prefix.
- Obscuration: Represents total sky obscuration where standard cloud layers cannot be identified.
7. Temperature and Dew Point: Displayed in Celsius (°C).
- Format: Always `Temperature/Dew Point` (e.g., 10/05).
- Temperature: The actual air temperature.
- Dew Point: The temperature to which air must be cooled to become saturated with water vapor, forming dew or fog. A smaller difference between temperature and dew point indicates higher humidity and a greater chance of fog or low clouds.
8. Pressure: Atmospheric pressure adjusted to sea level (QNH).
- USA / North America: Reported in inches of Mercury (inHg). Format: A3010 (30.10 inHg).
- International: Reported in Hectopascals (hPa). Format: Q1019 (1019 hPa).
- QFE: In some parts of the world, QFE (height above aerodrome) is reported in METAR.
9. Trend: Short-term forecast for the next 2 hours (found at the end of the report).
- NOSIG: No significant changes expected.
- TEMPO: Temporary fluctuations in weather conditions.
- BECMG: Gradual changes expected during the trend period.