Meteorological wind direction is the direction from which wind is blowing from.
Wind direction increases clockwise such that a north wind is 0°, an east wind is 90°, a south wind is 180°, and a west wind is 270°.
Because trigonometry uses a polar coordinate system in which 0° is along the x axis, the meteorology angle definition potentially wreaks havoc on typical angle calculations.
Fortunately, it is still easy to compute u and v given the meteorological wind angle. Let Φ be the meteorology wind direction angle, then the following equations can be applied:
Note that Φ must be in radians. If Φ is in degrees, multiply the angle by π/180 before using the trig function.
It is also possible to compute Φ from u and v using the atan2 function. The atan2 arguments vary by type of software.
On a spreadsheet, use the following equation to get an answer in degrees:
