National Weather Service United States Department of Commerce

Dangerous Cold Persists through Monday; Wintry Weather from the Northern Plains to the Great Lakes

Bitter cold temperatures and dangerous wind chills will persist from Florida to the Northeast through Monday. Daily record low temperatures are forecast across the Southeast and Florida, with some all-time February low temperature records possible across Florida. An Alberta clipper will spread wintry precipitation across the Northern Plains today and into the upper Great Lakes into tonight. Read More >

Overview

 

Severe thunderstorms developed across eastern Iowa and northwest Illinois Saturday, July 11, 2020, producing widespread wind damage and very large hail.

The first line of storms came through during the morning, producing damaging wind gusts and reports of quarter to ping pong ball size hail from Independence IA to Tipton IA. A wind gusts of 65 MPH was measured just west of Independence IA.

The second round of thunderstorms developed as a result of an upper level disturbance interacting with an atmosphere characterized by extremely high instability with modest vertical wind shear. Activity initially formed in north central Iowa, producing golf ball to two inch hail from Fort Dodge IA to Waterloo IA. Eventually, storms made their way towards the Cedar Rapids/Iowa City metros, producing widespread wind damage and hail up to baseball size. These storms continued through the Quad Cities metro east towards Princeton IL, Sterling IL and Hennepin IL, producing additional reports of wind damage and winds of 70-90 MPH. Numerous power outages were also reported.

 

Surrounding Office Event Summaries

NWS Chicago

Image
Sun Illuminating Striations and Mammatus Clouds After Squall Line Exited the Quad Cites Metro (Photo by David Cousins)