An unusually powerful low-pressure weather system swept through northern Illinois and northwest Indiana early Tuesday morning, resulting in over 300 canceled flights at O’Hare International Airport, more than 60,000 ComEd customers without power, and a spate of severe thunderstorm warnings and tornado watches throughout the Midwest.
No deaths were attributed to the storm, which was dubbed alternately a “chiclone” or the “windpocalypse” on news sites and in the blogosphere.
It was the second strongest storm ever to hit the Great Lakes area as measured by the barometric pressure at the storm’s center.
Late Tuesday the National Weather Service said a tornado with the maxium speed of 115 mph touched down about four miles east of Peotone in Will County, south of Chicago at 7:40 a.m. The tornado traveled 2.9 miles and caused downed power lines and partially destroyed a home. Another tornado is reported to have landed in Racine, Wis.
The massive storm, which generated wind speeds of up to 70 m.p.h., was the result of a low-pressure system that originated in Nebraska and intensified as it moved across the upper Midwest toward Canada, affecting 13 states.
"The storm system will be one of the most powerful we have seen in this part of the country in more than 70 years. This is a big deal," says Jim Allsopp, a meteorologist for the National Weather Service.
Holding the record for the lowest-pressure system ever to hit the Great Lakes is the Great Ohio Blizzard in January 1978, which buried homes across the Midwest with more than 40 inches of snow and measured 28.05 inches of mercury. At 28.41 inches of mercury, Tuesday’s storm surpasses the historic November 1975 storm over Lake Superior (28.95 inches) that sank the SS Edmund Fitzgerald.
Single engine planes were flipped on their sides at DuPage Airport in West Chicago. Flight delays are averaging 30 minutes each at O’Hare and Midway airports, says Karen Pride, a Chicago Department of Aviation spokesperson.
[Editor's note: A previous version of this story incorrectly reported that a woman had been killed outside Chicago. She was injured but survived.]