Its reported by the direction from which it originates. For example, a northerly wind blows from the south to the north. Wind direction is usually reported in cardinal directions or in azimuth degrees. For example, a wind coming from the south is given as 180 degrees; one from the east is 90 degrees.Wind Direction Scientists use both numbers and letters on a
compass to measure wind direction. On the compass below the letter N
stands for North, S stands for South, E stands for East, and W stands
for West. In order to be more specific, the letters NE are used for
Northeast, SE for southeast, SW for Southwest and NW for Northwest.