Decoding Guide
Wind Barb & Sky Coverage Notation

Wind speed and direction is indicated on standard charts by using Wind Barb Notation. A wind barb is a long stem originating from a Sky Coverage Symbol located at the observation point on the map. The stem points in the direction that the wind is blowing from. At the end of the stem, one or more flags indicate the wind speed. There are four types of flags that indicate 5, 10, 50, and 100 knot wind speeds. The absence of a stem indicates a zero wind speed. There are five sky coverage symbols which indicate the amount of cloud coverage.

 Four Basic Flags
  5 knots
   10 knots
   50 knots
   100 knots
 Sky Coverage Symbols
   Clear
   Few
   Scattered
   Broken
   Overcast

When more than one flags appear on a stem, the values are added to derive the total wind speed.

Examples:
  Wind from approx 200 degrees at 15 knots. Overcast skies.
  Wind from approx 220 degrees at 30 knots. Scattered Clouds.
  Wind from approx 250 degrees at 75 knots. Clear Skies.
  Wind from 270 degrees at 145 knots (upper air obs). Clear Skies.

 

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