Monday, May 12, 2014 Mike Smith

Two situations worthy of note:

I “issued” a special weather statement for Winnebago Co. At 2:47pm for 3/4 inch hail and gusts to 40 kts. Using ONLY surface obs and 1-minute satellite data.

At 2:59pm, I issued a severe thunderstorm storm warning for the same county, based on a Fujita U with overshooting then collapsing top in 1-minute data.

NWS issued severe at 2:56pm (unknown to me). Both warnings verified with 1.75” and 2.0” hail reports.

I observed a downburst south of Sullivan, WI and based on the right moving cell, I thought the RFD would intensify at 4:12pm for Walworth Co. Predicted 55 kt and 2” hail. Unknown if it verified.

The right mover got more pronounced and at 4:22pm, I issued a tornado warning for the southeast third of Walworth Co. This was due to the wrapping pattern of the outflow air (into RFD), the 1-minute satellite U and collapsing top, the persistent right movement and high spectrum width in the inflow. NWS issued a tornado warning for the same area at 4:45pm. While a pronounced hook formed, it never quite formed a tight couplet.