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Meteorology question: Cloud direction vs wind direction?

  1. Jul 20, 2012 #1
    Sometimes, but not always, the wind direction (as given by weather.com for my location) is exactly the opposite of the cloud movement. For example: the wind may be given as NW but the storm clouds are coming out of the SE. Almost always the wind direction given by weather.com is corroborated by the wind vane on the top of my house so I assume that weather.com is giving me the "ground level" wind direction. Am I correct in assuming that the upper atmosphere wind direction can be 180 degrees to the ground direction? I am aware that wind direction and wind speed can be different at different altitudes: jet streams.
  2. jcsd
  3. Jul 20, 2012 #2
    Winds circulate around low pressure areas due to the Coriolis effect and other forces. Ground winds are subject to drag due to ground obstacles, this slows it down reducing the Coriolis effect, as a result they turn into the direction of the low pressure and that's the main reason that surface winds have different directions than the upper winds (and hence clouds), but 180 degrees is a bit much, although the jet streams around 30,000 feet have also other, more complex logics.

    Question, can you figure out in which direction the surface wind turns, in comparison to the upper winds?
  4. Jul 20, 2012 #3
    Thanks. I'll have to think about your answer.

    Is this intended as a sort of homework question, meaning that the answer is the same for all locations in the northern hemisphere? Or do you want me to try to analyze my local weather/wind patterns?
  5. Jul 20, 2012 #4
    Ah the question is just to stimulate thinking, figuring things out. I could have explained it and I will eventually, if needed. But it's essentially the same on each hemisphere.
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