Overview of the April 4, 2011 Greene County, MS EF1 Tornado

During the late afternoon and evening of 4 April 2011, a fast moving and intense surface cold front (see Fig. 1 which is the surface front’s position valid at 4 PM CDT) plowed into a very warm, moist and unstable air mass that was in place over the north central Gulf Coast Region during the late afternoon and early evening hours. Immediately along and ahead of the surface cold front, a line of severe thunderstorms, already ongoing, moved into southeast Mississippi during the very late afternoon and progressed across southern Alabama and the extreme western Florida Panhandle by midnight (see Fig. 2a-c which is a progression of severe thunderstorm line between 6 PM and 11 PM). While the main event outcome was widespread damaging straight-line wind gusts over our entire region (Fig. 4), there was one rather long track EF-1 tornado that developed in association a supercell out ahead of the line and it occurred over Greene, Co. of southeast Mississippi (see radar photos, Fig. 3a-e, and tornado survey results).

In total, there was one confirmed and surveyed tornado, well over 50 reports of tree and power line damage, two reports of non-severe hail and 10 reports of gradient wind (i.e., non severe thunderstorm) tree damage during the daylight hours preceding the event. There was no associated event flash flooding given the very fast motion of the thunderstorms. This event will be remembered for its widespread wind damage across our area. Thankfully, there were no known deaths or injuries.
 

Surface Front’s Position Valid at 4 PM CDT
Fig. 1

Progression of Severe Thunderstorm Line at 23Z
Fig. 2a

Progression of Severe Thunderstorm Line at 2Z
Fig. 2b

Progression of Severe Thunderstorm Line at 5Z
Fig. 2c

TVS at 0044Z
Fig. 3a

TVS at 0049Z
Fig. 3b

TVS at 0054Z
Fig. 3c

TVS at 0058Z
Fig. 3d

TVS at 0103Z
Fig. 3e


 
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Damage Point legend


SPC Storm Reports for 4/4/2011
Fig. 4


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