For five lightning-punctuated hours centered on Friday evening’s rush-hour, wind-driven downpours pounded the Chicago area, unleashing the heaviest November calendar-day rainfall in 11 years. Thunderstorms are no strangers this time of the year. Sixty-two percent of Novembers since 1970—23 of the past 37 years—have hosted thunderstorms. But, the prolific lightning in Friday’s storms was exceptional. At the height of Friday’s storm, 160 cloud-to-ground strokes were observed in a single 15-minute period within 200 miles of Chicago. Doppler radar scans revealed a number of cloud tops exceeded 45,000 feet. Pea-sized hail which accompanied the storms actually covered the ground in several locations, among them Bolingbrook. Friday’s rain fell as wind chills hovered in the 30s and winds howled as high as 50 m.p.h.
The northern flank of the same storm buried sections of Iowa, Minnesota and Wisconsin under more than a foot of snow.
--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.
