How to Read METAR Reports

1. Introduction to METARs

METAR (Meteorological Aerodrome Report) is the international standard format for reporting weather observations at airports and weather stations worldwide. Understanding how to read METARs is an essential skill for every pilot, from student pilots to airline captains.

METARs provide a snapshot of current weather conditions including wind, visibility, precipitation, cloud cover, temperature, dewpoint, and barometric pressure. This information is critical for:

• Pre-flight planning - Determining if conditions meet VFR or IFR requirements
• Go/no-go decisions - Assessing whether it's safe to fly
• Approach planning - Knowing what to expect at your destination
• Fuel planning - Headwind/tailwind components affect fuel burn
• Alternate selection - Comparing weather at potential alternates

2. METAR Format Overview

Every METAR follows a standardized format established by the International Civil Aviation Organization (ICAO). Here's a typical METAR broken down into its components:

Let's break this down:

3. Station Identifier

Every METAR begins with a 4-letter ICAO airport identifier. In the United States, these codes start with "K" (contiguous US), "P" (Pacific including Alaska and Hawaii), or "T" (Caribbean). Examples:

• KJFK - New York JFK (K + FAA code JFK)
• EGLL - London Heathrow (E = Northern Europe, G = UK)
• LFPG - Paris Charles de Gaulle (L = Southern Europe, F = France)
• RJTT - Tokyo Haneda (R = East Asia, J = Japan)

You can search for any airport's weather on MetarCentral using the ICAO code. Try searching for an airport →

4. Date and Time

The date/time group consists of 7 characters in the format DDHHMMZ:

• DD - Day of the month (01-31)
• HH - Hour (00-23)
• MM - Minutes (00-59)
• Z - Zulu time (UTC)

For example, 251856Z means the 25th day of the month at 18:56 UTC.

METARs are typically issued at 55 minutes past each hour (routine observations). Special observations (SPECI) can be issued at any time when significant weather changes occur.

5. Wind Information

Wind is one of the most critical elements for pilots. The format is:

Where:

• ddd - Wind direction in degrees true (3 digits)
• ss - Wind speed (2-3 digits)
• Ggg - Gust speed (if present)
• KT - Knots (or MPS for meters per second)

Wind Examples:

Variable wind directions may be reported as 180V240 indicating the wind is varying between 180° and 240°.

6. Visibility

Visibility tells you how far you can see horizontally. The format differs between US and international METARs:

US METARs (Statute Miles):

• 10SM - 10 statute miles (good visibility)
• 6SM - 6 statute miles
• 3SM - 3 statute miles (MVFR threshold)
• 1SM - 1 statute mile (IFR threshold)
• 1/2SM - Half statute mile (LIFR threshold)
• 1/4SM - Quarter statute mile

International METARs (Meters):

• 9999 - 10 kilometers or more (unlimited)
• 5000 - 5,000 meters (about 3 miles)
• 0800 - 800 meters (about half mile)

Visibility is critical for determining flight categories (VFR, MVFR, IFR, LIFR).

7. Weather Phenomena

Weather phenomena are reported using standardized abbreviations. They can include intensity prefixes and descriptors:

Intensity:

• - (minus) Light
• (no symbol) Moderate
• + (plus) Heavy
• VC In the vicinity (5-10 miles from airport)

Descriptors:

Precipitation:

Obscurations:

Common Examples:

• -RA - Light rain
• +TSRA - Heavy thunderstorm with rain
• SHRA - Rain showers
• FZRA - Freezing rain
• BR - Mist (visibility 5/8 to 6 miles)
• FG - Fog (visibility below 5/8 mile)
• VCSH - Showers in vicinity

8. Cloud Layers

Cloud coverage is reported using sky condition codes plus height in hundreds of feet AGL (above ground level):

Cloud Examples:

• FEW020 - Few clouds at 2,000 feet AGL
• SCT045 - Scattered clouds at 4,500 feet AGL
• BKN008 - Broken clouds at 800 feet AGL (this is the ceiling)
• OVC002 - Overcast at 200 feet AGL
• VV003 - Vertical visibility 300 feet (sky obscured)
• SCT025CB - Scattered cumulonimbus at 2,500 feet
• BKN040TCU - Broken towering cumulus at 4,000 feet

9. Temperature and Dewpoint

Temperature and dewpoint are reported in degrees Celsius, separated by a slash:

Examples:

• 24/18 - Temperature 24°C, Dewpoint 18°C
• M02/M05 - Temperature -2°C, Dewpoint -5°C (M = minus)
• 15/15 - Temperature equals dewpoint (100% humidity, fog likely)

The temperature-dewpoint spread tells you about moisture and fog potential:

• Spread > 10°C - Low humidity, fog unlikely
• Spread 3-5°C - Moderate humidity, watch for fog development
• Spread < 3°C - High humidity, fog or mist likely

10. Altimeter Setting

The altimeter setting allows you to calibrate your altimeter for accurate altitude readings:

US Format (inches of mercury):

• A3012 - Altimeter 30.12 inches Hg
• A2992 - Standard pressure (29.92 inches Hg)
• A2875 - Low pressure (28.75 inches Hg)

International Format (hectopascals/millibars):

• Q1013 - Altimeter 1013 hPa (standard pressure)
• Q0998 - Altimeter 998 hPa (low pressure)
• Q1025 - Altimeter 1025 hPa (high pressure)

11. Remarks Section (RMK)

The remarks section contains additional information not included in the main body. Common remarks include:

Station Type:

• AO1 - Automated station without precipitation discriminator
• AO2 - Automated station with precipitation discriminator

Sea Level Pressure:

• SLP203 - Sea level pressure 1020.3 hPa
• SLP982 - Sea level pressure 998.2 hPa

Hourly Precipitation:

• P0015 - 0.15 inches of precipitation in the last hour

Temperature (Precise):

• T02340189 - Temperature 23.4°C, Dewpoint 18.9°C

Peak Wind:

• PK WND 28045/1923 - Peak wind from 280° at 45 knots at 19:23Z

12. Real METAR Examples

Example 1: VFR Conditions

Decoded: Chicago O'Hare, 25th at 1951Z. Wind from 360° at 12 knots. Visibility 10 miles. Few clouds at 25,000 feet. Temperature 22°C, dewpoint 11°C. Altimeter 30.01". Automated station. Sea level pressure 1016.4 hPa. VFR conditions.

Example 2: IFR Conditions

Decoded: San Francisco, 25th at 1856Z. Wind from 280° at 8 knots. Visibility 2 miles in mist. Overcast at 600 feet (ceiling). Temperature 14°C, dewpoint 12°C. Altimeter 29.98". IFR conditions - ceiling below 1000 feet.

Example 3: Severe Weather

Decoded: Dallas-Fort Worth, 25th at 1853Z. Wind from 180° at 25 knots gusting to 40. Visibility 1/2 mile in heavy thunderstorm with rain. Broken clouds at 800 feet, overcast cumulonimbus at 1,500 feet. Temperature 24°C, dewpoint 23°C (very humid). Altimeter 29.65" (low pressure). LIFR conditions with convective activity.