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Derecho Slams Chicago, 600k Lose Power, Record Tornadoes

8/12/2026

50 7 Full Breakdown

Summary

Chicago Storms

Thunderstorms and two EF-1 tornadoes hit Chicago and its south suburbs on Aug 11 2026, causing damage.
Wind gusts peaked at 100 mph, with 99 mph recorded in Gary, Indiana.
Power outages affected 600,000 customers in Illinois and Indiana, including 69 % of Homewood residents.
O’Hare Airport saw a 45 % delay rate and a 10 % cancellation rate after a ground stop.
Illinois logged a record 220 tornadoes through July, far above the 54-year average.

Summary

Derecho Ravages Midwest

The storm system was classified as a derecho, meeting a 250-mile length and a 60-mile width.
The Storm Prediction Center issued a Level 3 severe storm risk for the Midwest and Ohio Valley.
Weather Service warned wind gusts could top 90 mph as radar showed rotation in the squall line.
Forecasts warned rainfall could exceed 6.5 inches, prompting a flash-flood emergency in Perry County, Ohio, expiring at 3 a.m.

History

Historical Context

The June 6-7 1998 Midwest derecho ripped across Illinois, Indiana and Ohio, spawning 19 tornadoes, a 100 mph wind gust in Iowa and one fatality. Like that event, the August 2026 thunderstorms and EF-1 tornadoes have battered Chicago, Gary and Homewood, reviving concerns about the region’s recurring derecho-type hazards and prompting the NWS and SPC to issue enhanced warnings.

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Chicago Storms

Thunderstorms and two EF-1 tornadoes hit Chicago and its south suburbs on Aug 11 2026, causing damage.
Wind gusts peaked at 100 mph, with 99 mph recorded in Gary, Indiana.
Power outages affected 600,000 customers in Illinois and Indiana, including 69 % of Homewood residents.
O’Hare Airport saw a 45 % delay rate and a 10 % cancellation rate after a ground stop.
Illinois logged a record 220 tornadoes through July, far above the 54-year average.

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