Every five seconds an updated 2-minute average wind direction and wind speed are calculated from the twenty-four 5-second averages produced during the past 2 minutes.


Two-minute averages are rounded to the nearest knot and nearest degree.
For example, if the 5-second average wind values (12 per minute) were:

minute 1 3 4 2 5 7 6 4 2 4 6 5 5
minute 2 6 3 4 7 4 5 3 5 2 5 6 4

The 7 missing 5-second average wind values would result in a 'missing' 2-minute average wind speed and direction.

If more than six 5-second averages are missing during the two minute calculation period, the 2-minute average wind values are marked missing.
As an example, if the 5-second average wind values (12 per minute) were:

minute 1 3 M 2 5 M 6 4 2 4 6 M M
minute 2 6 3 4 M 4 M 3 5 M 5 6 4

The sum of 107 gives a 2-minute average wind speed of 4.45, or 4 knots, rounded to the nearest knot.