National Weather Service United States Department of Commerce

Dangerous Heat Continues; Monitoring Excessive Rainfall and Flash Flooding

The heat continues along and east of the Mississippi River. The most significant cumulative heat impacts are expected across the Mid-Atlantic through today and eastern Ohio Valley through Friday. Severe weather and heavy rainfall potential from the Southwest, Plains, upper Midwest, Great Lakes, mid-Atlantic and Northeast the next couple of days. A disturbance near the Marianas may bring flooding. Read More >

Overview

It was a very active afternoon and evening across eastern Iowa and northwest Illinois Thursday afternoon and evening, as a disturbance and trailing cold front moved into the area from the west. This disturbance and front interacted with a hot, humid and very unstable atmosphere, leading to development of showers and thunderstorms. 

Storms that developed in the early afternoon took advantage of the very high instability, and had no trouble becoming strong, an even severe, in a short amount of time. Storms initially formed along and north of the Highway 30 corridor in eastern Iowa, and produced widespread damage to crops in Buchanan and Delaware counties, and eventually went on to produce a wind gust near 60 MPH at the Dubuque Regional Airport. Storms across this area eventually merged and slowed down, leading to localized rainfall amounts of 4 - 5 inches. This very heavy rainfall produced flash flooding in the Dubuque metro, with law enforcement reporting several road closures along Highway 20.

Storms continued to form along a line to the south through the mid afternoon, and reached the Mississippi River around 6 - 7 PM. Several reports of wind damage to trees were received from McDonough county to the Quad Cities metro. A few reports of funnel clouds were also received from the Kirkwood IL area, but no tornado was ever observed.

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Severe Thunderstorm Watch #348 Graphic