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

Notations 5 knots
Notations 10 knots
Notations 50 knots
Notations 100 knots

Sky Coverage Symbols

Notations Clear
Notations Few
Notations Scattered
Notations Broken
Notations Overcast
When more than one flags appear on a stem, the values are added to derive the total wind speed.


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