How to Read METAR Reports: The Complete Guide for Pilots
Understanding METAR (Meteorological Aerodrome Report) is one of the most essential skills for any pilot, flight dispatcher, or aviation enthusiast. Whether you are a student pilot learning the basics or an experienced aviator refreshing your knowledge, this comprehensive guide will walk you through every element of a METAR report with real-world examples and practical tips.
What is a METAR Report?
A METAR is a standardized weather observation report issued by airports and weather stations around the world. Published at regular intervals, typically every 30 to 60 minutes, METAR reports provide a snapshot of current atmospheric conditions at the observation point. The format follows standards set by the International Civil Aviation Organization (ICAO) and the World Meteorological Organization (WMO), ensuring consistency across international borders.
METAR reports are the backbone of aviation weather briefings. Pilots rely on them for pre-flight planning, approach decisions, and diversion assessments. Air traffic controllers use them to manage traffic flow, and dispatchers incorporate them into flight release calculations.
METAR Format Breakdown
A standard METAR report follows this structure:
METAR KJFK 151756Z 31015G25KT 10SM FEW045 SCT250 24/11 A3002 RMK AO2 SLP168
1. Report Type
METAR indicates a routine scheduled observation. SPECI indicates a special unscheduled report triggered by significant weather changes such as rapid visibility drops, wind shifts, thunderstorm onset, or ceiling changes that cross flight category thresholds.
2. Station Identifier
KJFK is the ICAO four-letter identifier for John F. Kennedy International Airport. In the United States, identifiers begin with K. In Canada, they start with C. European stations often begin with E (UK: EG, Germany: ED, France: LF). Knowing these prefixes helps you quickly identify the region when scanning multiple reports.
3. Date and Time
151756Z means the 15th day of the month at 17:56 UTC (Zulu time). All METAR times use UTC to avoid confusion across time zones. The Z suffix confirms Zulu time. Converting to local time requires knowing the station time zone offset.
4. Wind
31015G25KT decodes as wind from 310 degrees (northwest) at 15 knots, gusting to 25 knots. Key wind variations include:
- VRB05KT – Variable direction at 5 knots (light and shifting winds)
- 00000KT – Calm winds (no measurable wind)
- 24015KT 180V300 – Wind from 240 at 15 knots, direction varying between 180 and 300 degrees
- 27045G60KT – Severe wind from 270 at 45 knots gusting 60 (likely storm conditions)
5. Visibility
10SM means 10 statute miles visibility, which is effectively unlimited for aviation purposes. In countries using metric measurements, visibility is reported in meters (e.g., 9999 means 10 km or more). Low visibility values directly determine flight category classifications.
6. Weather Phenomena
Weather descriptors appear between visibility and cloud groups. Common codes include:
- RA – Rain | SN – Snow | DZ – Drizzle
- FG – Fog | BR – Mist | HZ – Haze
- TS – Thunderstorm | SH – Showers
- + prefix – Heavy intensity | – prefix – Light intensity
- FZ prefix – Freezing (FZRA = freezing rain, FZFG = freezing fog)
7. Cloud Cover
FEW045 SCT250 indicates few clouds at 4,500 feet AGL and scattered clouds at 25,000 feet AGL. Cloud coverage levels are:
- SKC/CLR – Sky clear (no clouds)
- FEW – Few (1/8 to 2/8 coverage)
- SCT – Scattered (3/8 to 4/8 coverage)
- BKN – Broken (5/8 to 7/8 coverage) – this is a ceiling
- OVC – Overcast (8/8 coverage) – this is a ceiling
Only BKN and OVC layers constitute a ceiling. The ceiling height is critical for determining flight categories: VFR requires a ceiling above 3,000 feet, while IFR conditions exist when the ceiling is between 500 and 999 feet.
8. Temperature and Dew Point
24/11 means temperature 24 degrees Celsius, dew point 11 degrees Celsius. When temperature and dew point converge (spread less than 3 degrees), fog or low clouds are likely to form. A prefix M indicates minus (below zero), for example M02/M05 means minus 2 temperature and minus 5 dew point.
9. Altimeter Setting
A3002 means the altimeter setting is 30.02 inches of mercury (inHg). In metric regions, this is reported as QNH in hectopascals, for example Q1013. Setting the correct altimeter is critical for accurate altitude readings and terrain clearance.
Flight Category Determination from METAR
Flight categories are determined by the lowest ceiling and prevailing visibility reported in the METAR:
- VFR: Ceiling above 3,000 ft AND visibility greater than 5 SM
- MVFR: Ceiling 1,000-3,000 ft AND/OR visibility 3-5 SM
- IFR: Ceiling 500-999 ft AND/OR visibility 1 to less than 3 SM
- LIFR: Ceiling below 500 ft AND/OR visibility below 1 SM
Common METAR Reading Mistakes
Even experienced pilots sometimes misread METARs. Watch out for these common pitfalls:
- Confusing AGL (above ground level) cloud heights with MSL (mean sea level) altitude
- Forgetting that visibility in the US is in statute miles, not nautical miles
- Missing the variable wind direction group after the main wind report
- Not checking the remarks section for important supplementary information
- Overlooking SPECI reports that indicate rapidly changing conditions
Practice Reading METARs on METAR&TAF
The best way to improve your METAR reading skills is practice. On METAR&TAF, you can view decoded METAR reports for over 1,600 airports worldwide, with color-coded flight categories and plain-language translations. Our interactive map makes it easy to compare conditions across regions and identify weather patterns.
