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A white enclosed gyroplane in flight over countryside

Ground school lesson

Reading a METAR

METAR KAPA 241753Z 18012G18KT 10SM SCT070 28/09 A3002 looks like line noise. It is actually the most information-dense sentence in aviation, and decoding it is entirely mechanical.

My Hangar

Lesson 14 of 27 · 3 steps · about 7 minutes · ends with a quiz

What you will be able to do

  • Break any METAR into its fixed field order.
  • Decode wind, visibility, sky condition and temperature.
  • Spot the two fields that most often cancel a gyroplane flight.

  1. Step 1 of 3

    The fields always come in the same order

    A METAR is an hourly observation from a station, written in a fixed sequence. Because the order never changes, you decode by position, not by guessing.

    A METAR decoded field by field The report METAR KAPA 241753Z 18012G18KT 10SM SCT070 28/09 A3002 with each field labelled: station, day and time, wind, visibility, clouds, temperature and dew point, altimeter. METAR KAPA 241753Z 18012G18KT 10SM SCT070 28/09 A3002 station: Centennial 24th, 17:53 UTC wind 180° at 12, gusting 18 kt 10 miles scattered at 7,000 ft AGL 28°C / dew 9°C altimeter 30.02 inHg Same order, every report, every station.
    One real-format report, labelled. Decode left to right and nothing is mysterious.

  2. Step 2 of 3

    The codes you will actually meet

    CodeMeans
    18012G18KTWind from 180° true at 12 knots, gusting 18. VRB means variable direction; 00000KT is calm.
    10SMVisibility 10 statute miles. Below 3SM a sport pilot stays on the ground.
    CLR / FEW / SCT / BKN / OVCSky cover, thinnest to thickest, each with a height in hundreds of feet AGL. BKN and OVC form a ceiling.
    28/09Temperature 28°C, dew point 9°C. Close together means fog risk; far apart on a hot day means density altitude.
    A3002Altimeter setting 30.02 inHg. What you dial in, and one input to density altitude.
    RA / TS / BR / -/+Weather: rain, thunderstorm, mist. A minus or plus prefix is intensity. TS anywhere in the report ends the discussion.

  3. Step 3 of 3

    What a gyroplane pilot reads first

    Every field matters, but two decide most go/no-go calls for a light rotorcraft:

    The G in the wind group

    A gust spread of more than a few knots matters more to a gyroplane than the steady number. 12G18 is a 6-knot spread; run it against the crosswind lesson and your personal minimums.

    Temperature against the field

    A hot temperature at an already-high field is the density altitude trap. Feed it to the density altitude calculator before you trust the runway length.

    Practice free, forever. Every US METAR is public at aviationweather.gov. Pull your home field's report each morning and decode it until the code reads like a sentence. It takes about a week.

Check yourself

3 questions. Pick an answer to see whether it is right and why.

  1. In 18012G18KT, what does the G mean?

  2. Which sky covers create a ceiling?

  3. A METAR reads 2SM in the visibility field. Can a sport pilot fly?

Reading and practice are free. Create an account to save progress and private notes.

FAA Aviation Weather Handbook and Pilot's Handbook of Aeronautical Knowledge (public domain). Live reports: aviationweather.gov.