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Weather Data : METAR and TAF

METAR = METeorological Aerodrome Report

TAF = Terminal Area Forecast

Both are** coded weather reports, a **METAR is an observation (now), a TAF is a forecast (future, up to 30 hours ahead). Both use a similar format and abbreviations.

These weather products can be obtained from aviationweather.gov or 1800WXbrief.com by entering the desired airport’s 4 letter identifier code ( i.e KLAX, KSFO)

Small airports may not deliver METARs or TAFs, and TAFs are usually only available at larger airports.

Unfortunately for those new to aviation, the FAA wants remote-pilots to learn how to read raw METARs and TAFs, you can expect 1 to 3 questions covering these on the test. For real world use, these are available in a plain language format (decoded) and are a great tool to obtain accurate weather information.

Remember this for the knowledge test:

  • Wind directions are reported in *true heading. *
  • Cloud **heights are reported in hundreds of feet above ground level.**
  • A cloud ceiling is a broken or overcast cloud layer.

Examples and decoding table below. For more details consult:

A raw METAR looks like this:

KIAD 180005Z 19008KT 10SM TS SCT060CB BKN090 BKN200 31/21 A3002 RMK AO2 TSB04 FRQ LTGICCCCG SW TS SW MOV NE T03060211

Below is the same METAR in decoded format:

METAR for: KIAD (Washington/Dulles In, VA, US)
Date and Time: the 18th of the current month at 00:05 UTC (Universal Time Coordinated)
Winds: from the S (190 degrees) at 9 MPH (8 knots; 4.1 m/s)
Visibility: 10 or more sm (16+ km)
Weather: TS (thunderstorm)
Clouds: scattered cumulonimbus clouds at 6000 feet AGL, broken clouds at 9000 feet AGL, broken clouds at 20000 feet AGL
Temperature: 30.6°C ( 87°F)
Dewpoint: 21.1°C ( 70°F) [RH = 57%]
Pressure (altimeter): 30.02 inches Hg (1016.7 mb)

Sample TAF:

KIAD 172349Z 1800/1906 21005KT 6SM -TSRA BR OVC040CB

TEMPO 1800/1802 26020G35KT 1/2SM +TSRA FG OVC030CB

FM180300 VRB03KT 6SM -SHRA BR VCTS OVC040CB

FM180600 00000KT P6SM VCSH OVC060

FM181300 32006KT P6SM SCT050 SCT150

Decoded TAF:

METAR for: KIAD (Washington/Dulles In, VA, US)
Text: KIAD 180005Z 19008KT 10SM TS SCT060CB BKN090 BKN200 31/21 A3002 RMK AO2 TSB04 FRQ LTGICCCCG SW TS SW MOV NE T03060211
Winds: from the S (190 degrees) at 9 MPH (8 knots; 4.1 m/s)
Temperature: 30.6°C ( 87°F)
Dewpoint: 21.1°C ( 70°F) [RH = 57%]
Pressure (altimeter): 30.02 inches Hg (1016.7 mb)
Visibility: 10 or more sm (16+ km)
Ceiling: 9000 feet AGL
Clouds: scattered clouds at 6000 feet AGL, broken clouds at 9000 feet AGL, broken clouds at 20000 feet AGL
Weather: TS (thunderstorm)
TAF for: KIAD (Washington/Dulles In, VA, US) issued at 2349 UTC 17 Aug 2016
Text: KIAD 172349Z 1800/1906 21005KT 6SM -TSRA BR OVC040CB
Forecast period: 0000 to 0300 UTC 18 August 2016
Forecast type: FROM: standard forecast or significant change
Winds: from the SSW (210 degrees) at 6 MPH (5 knots; 2.6 m/s)
Visibility: 6 sm ( 10 km)
Ceiling: 4000 feet AGL
Clouds: overcast cloud deck at 4000 feet AGL
Weather: -TSRA BR (light rain associated with thunderstorm(s), mist)
Text: TEMPO 1800/1802 26020G35KT 1/2SM +TSRA FG OVC030CB
Forecast period: 0000 to 0200 UTC 18 August 2016
Forecast type: TEMPORARY: The following changes expected for less than half the time period
Winds: from the W (260 degrees) at 23 MPH (20 knots; 10.3 m/s) gusting to 40 MPH (35 knots; 18.0 m/s)
Visibility: 0.50 sm ( 0.80 km)
Ceiling: 3000 feet AGL
Clouds: overcast cloud deck at 3000 feet AGL
Weather: +TSRA FG (heavy rain associated with thunderstorm(s), fog)
Text: FM180300 VRB03KT 6SM -SHRA BR VCTS OVC040CB
Forecast period: 0300 to 0600 UTC 18 August 2016
Forecast type: FROM: standard forecast or significant change
Winds: variable direction winds at 3 MPH (3 knots; 1.5 m/s)
Visibility: 6 sm ( 10 km)
Ceiling: 4000 feet AGL
Clouds: overcast cloud deck at 4000 feet AGL
Weather: -SHRA BR VCTS (light rain showers, mist, thunderstorm in vicinity)
Text: FM180600 00000KT P6SM VCSH OVC060
Forecast period: 0600 to 1300 UTC 18 August 2016
Forecast type: FROM: standard forecast or significant change
Winds: calm
Visibility: 6 or more sm (10+ km)
Ceiling: 6000 feet AGL
Clouds: overcast cloud deck at 6000 feet AGL
Weather: VCSH (showers in vicinity)
Text: FM181300 32006KT P6SM SCT050 SCT150
Forecast period: 1300 UTC 18 August 2016 to 0600 UTC 19 August 2016
Forecast type: FROM: standard forecast or significant change
Winds: from the NW (320 degrees) at 7 MPH (6 knots; 3.1 m/s)
Visibility: 6 or more sm (10+ km)
Ceiling: at least 12,000 feet AGL
Clouds: scattered clouds at 5000 feet AGL, scattered clouds at 15000 feet AGL

Use the following decoding table from NOAA and the FAA:

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Practice decoding the METARs and TAFs from the Airman Knowledge Testing Supplement in figures 12 and 15.

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