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Strong Winds Over West Alabama

| January 10, 2013 @ 7:30 pm

Strong winds are reported over much of West Alabama this evening… on the back side of a departing rain mass…

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Trees have been blown in a few spots over Sumter and Pickens Counties; from most reports it seems like winds are averaging 35-45 mph, with higher gusts.

LATE NOTE: We just recorded a peak wind gust of 57 mph atop the Tuscaloosa County Courthouse. Now getting reports of trees down across Tuscaloosa and Fayette Counties…

The band of high winds will move east, and could possibly impact the Birmingham metro by 8:45-9:00 p.m. The period of high wind lasts about 15 minutes, followed by a slow decrease in wind speed.

These highs winds are NOT related to thunderstorms directly…

The winds are the result of a wake low/gravity wave combination… I think Kirk Mellish has a good simple explanation…

“A big complex of rain and thunderstorms can push up a lot of air, it then falls back to earth, which causes a rapid change in temp and air pressure over a short distance putting the atmosphere out of balance, the wind accelerated as nature tried to get the atmosphere back in balance or equilibrium. A small mountain of air (high) was followed by a hole in the air (low). The wind rushed from the mountain to fill the hole. The steeper the grade or gradient between the two the harder the climb or the harder the wind. Nature trys to equal out the two to reach a flat known as a stasis. Ocean waves are another example. A rock dropped into a lake and the resulting splash and waves that radiate out from it are another example.”

We are better at identifying wake low/gravity wave setups, but often it can happen without any warning. This is an entirely different process than winds directly from thunderstorms.

The winds will die down later this evening…

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Category: Alabama's Weather

About the Author ()

James Spann is one of the most recognized and trusted television meteorologists in the industry. He holds the AMS CCM designation and television seals from the AMS and NWA. He is a past winner of the Broadcast Meteorologist of the Year from both professional organizations.

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