Three Days of Dangerous Storms

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Extremely active weather across the eastern half of the United States the next three days.

This Afternoon and Tonight

 This is the difficult forecast. The Storm Prediction Center provided the base map which shows a large area of 5% tornado chances (that is the significant threshold). I have added the red box which is where I believe the higher chances of tornadoes exist. However, this is one of those forecasts where there will either be very strong thunderstorms in this region or nothing at all.

Here is the forecast for large hail. The hatched area, given that thunderstorms develop, may have hail larger than 2" in diameter.


Thursday and Thursday Night
The "significant" threshold on this map is 15% (yellow) and you can see the probabilities are considerably higher for tornadoes, damaging thunderstorm winds and tornadoes. In the hatched area, violent tornadoes and giant hail are possible. It would not surprise me if more than ten tornadoes occur over this region.

Friday and Friday Night
Other Threats

A flash flood watch is in effect for parts of Illinois and Indiana. This may be expanded into the northern half of Missouri before the storms are over. Take this threat seriously as multiple rounds of thunderstorms with heavy rains are likely in this region.

And, winter refuses to let go. The deep green color is a winter storm watch for heavy snow. Blue is a travel advisory.
I will be updating the blog on today's severe weather threat.

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