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Wind direction increases clockwise such that a north northerly wind is 0°, an east easterly wind is 90°, a south southerly wind is 180°, and a west westerly wind is 270°.
Because trigonometry uses a polar coordinate system in which 0° is along the x axis, the meteorology meteorological angle definition potentially wreaks can wreak 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 meteorological wind direction angle, then the following equations can be applied:
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