The wind rating is based upon the average wind speed at your location. We use average values for each month. It is measured in meters-per-second (m/s). 1 m/s is about 2.2 mph
We reference NASA Surface meteorology data from the Atmospheric Data Center. This data is based upon satellite-derived data over a 22-year period. The data is compiled for each degree of latitude and longitude (each degree represents about 69 ground miles).
Reference Height: The wind speeds are for a reference height of 50 m (164 ft) for USA locations and 10m (13 ft) for Canadian locations.
Note: Because wind varies, sometimes dramatically, from location to location the wind rating provided is only an estimate. Elevation, trees, mountains, valleys, thermal variations and other geographic and weather pattern factors will affect the actual wind you will realize at your location.
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