Saturday's Severe Storm Verification

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Saturday, we forecast very large hail and damaging winds over a large part of the central United States. How did that forecast work out? The answer is: B-.

Hail Forecast
These are the actual reports of hail 1" or larger superimposed on the forecast. Triangles are hailstones 2" or larger. Along the Kansas hail path, there was softball-sized hail from just southwest of Topeka to I-35. Those fell in the red, hatched area -- a very good forecast.

There was also very large hail over the Midwest. A red area should have been forecasted to correspond to the geographic density of the hailfall.

Wind Forecast
Dots are wind speeds of 58 mph (50 knots) or higher. Squares are gusts of 75 mph or more. The red forecast was a little too far north and east. That resulted in areas like Wichita being in the higher risk area without receiving even rain and not adequately covering the wind threat into Oklahoma and Texas.

The Midwest derecho should have been covered with a hatched area and with even higher probabilities than 30%.

The ideal forecast would have also been broken in two as there as little severe weather occurred in Missouri and Arkansas.

My characterization? "Not bad, but certainly not perfect."

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