WW2010
University of Illinois

WW2010
 
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4/19 IL Tornadoes
 
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How It Happened
 
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Turning Winds With Height
a key ingredient to tornado outbreak

The vertical wind profile discussed previously was evident here on the 00Z, or 7:00 PM sounding. The column of wind barbs on the right side of the image are the wind observations recorded at various pressure levels of the atmosphere.

[Image: 0000 4/20 ILX sounding (42K)]

The sounding shows that winds were primarily from the south near the surface but veered around to a more west-southwesterly direction at mid levels. In addition to the directional shear, some speed shear is evident in the wind profile, as 30 knot low level winds increased to 50 knots at mid levels.



wind shear
Terms for using data resources. CD-ROM available.
Credits and Acknowledgments for WW2010.
Department of Atmospheric Sciences (DAS) at
the University of Illinois at Urbana-Champaign.

convergence