Friday afternoon and evening’s lightning-packed, wind-gushing thunderstorms raced across the Chicago area at 45 miles per hour after a vicious 800-mile 24-hour-plus trek out of the western Plains. Rare is the squall line able to survive over such a long period of time. After unleashing a swarm of as many as 13 twisters around midday Friday—tornadoes which hit areas just west of the Quad Cities with building-flattening force—the squall line took nine hours to cross northern Illinois, where its clouds towered to 52,000 feet, and 40+ m.p.h. gusts blasted Chicago’s west/northwest suburbs. Gusts to 60 m.p.h. were clocked at Kane County’s Maple Park, 54 m.p.h. at Naperville, and 44 m.p.h. at Lombard. Over a single hour Friday afternoon, cloud-to-ground lightning flashed more than 3,000 times. Rainfall fell so heavily in the Sterling/Rock Falls area of northwest Illinois—1.67” in just 30 minutes—serious flooding resulted. The Rockford area was drenched by 1” of rain.
--By Tom Skilling, WGN-TV Chief Meteorologist
WGN-TV Chief Meteorologist Tom Skilling and the WGN Weather Center staff provide daily coverage of weather in the Chicago area.
