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Anatomy of a complex forecast: Today

 
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windfind



Joined: 18 Mar 1997
Posts: 1899

PostPosted: Wed Apr 28, 2021 1:04 pm    Post subject: Anatomy of a complex forecast: Today Reply with quote

Hi Gang,

I am not your forecaster today but I am still tracking the variables since I will be forecasting tomorrow.

Years ago a customer said he could not understand why it was so hard to make good wind forecasts. After all, all you need to know is the pressure gradient.

There is some truth to that since ultimately it is the pressure gradient from higher pressure to lower pressure that drives our wind. And IF the Flat Earth people were right and IF the earth had zero topography and IF the atmosphere was 2D rather than 3D... then the major variable you would need to know to forecast wind would be the pressure gradient.

So, the animation shows some of the complexity in actual forecasting. Note that while most of you will be kiting or windsurfing in NW or WNW or WSW winds the actual winds today that will shape our winds come from every point on the compass. AND this animation is only 2D. When forecasting we have to consider winds from 18,000 ft to 1000 ft. aloft.

As you look at this animation imagine that... the eddy does not die. The Northerly winds in the valley do not fade, the Hwy. 92 gaps SW winds are stronger than forecast etc...

Enjoy,

Mike Godsey
iwindsurf/ikitesurf



Bay complex edy forecast.2021-04-28 10_53_57.gif
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Bay complex edy forecast.2021-04-28 10_53_57.gif


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