Thunderstorm Wind in Butler County, Iowa

Coop observer reported very high winds estimated at over 70 mph. Power reported out in Parkersburg, semi overturned on Highway 57 resulting in one fatality, and numerous tree limbs down on roads. A 3 foot diameter tree also downed in Parkersburg.

After a cold front stalled out across northwest Iowa the previous night, much of Iowa was firmly within the warm sector of an approaching surface low. As a result, winds were strong out of the south, helping keep dew points in the mid to upper 60s. While temperatures were only in the 70s, with the relatively high dew points SBCAPE values were able to eclipse 2000 J/kg in an uncapped environment. Storms began to initiate in the early afternoon, primarily producing funnel clouds and hail. As a weak boundary ahead of the parent cold front moved through, storms organized linearly and became primary wind gust and damaging wind producers as they traveled north/northeast.