Full Breakdown
Massive Derecho and Tornado Outbreak Ravages Chicago Area
8/12/2026, 11:55:47 AM
Core Event – August 11, 2026 Derecho and Tornadoes
On Tuesday, August 11, 2026, a fast-moving line of severe thunderstorms swept from eastern Iowa across northern Illinois, the Chicago metro area, and into northern Indiana. The Storm Prediction Center preliminarily classified the system as a derecho, and the National Weather Service confirmed three EF-1 tornadoes in the Chicago region: one in southern Cook County, a second in eastern Will County, and a third near Mokena. Wind gusts reached 99 mph in Gary, Indiana, with similar reports elsewhere.
Background & Context
The 2026 tornado season has been unusually active, with Illinois nearing 200 tornadoes. Meteorologists said high humidity, strong low-level winds and a lingering boundary created an unsettled pattern that set the stage for the event.
Data & Statistics
- Power outages: Nearly 1 million customers lost electricity across Illinois, Indiana and Ohio, later narrowed to about 357,000 ComEd customers in northern Illinois and 301,000 NIPSCO customers in northwest Indiana.
- Wind: Measured gusts topped 99 mph in Gary; other locations reported 86-110 mph.
- Tornadoes: Three EF-1 tornadoes confirmed with damage paths in southern Cook County, eastern Will County and the Mokena area.
- Fatalities: Two deaths were linked to delayed emergency care on clogged roads; a suspected house explosion in Portage claimed one life.
- Aviation: Ground stops at O’Hare and Midway halted departures until mid-morning; about 250 flights were canceled at O’Hare and nearly 300 overall.
Impact on Infrastructure and Communities
Tree loss, roof damage and downed power lines were reported from the southwest side of Chicago through the southern suburbs. Oak Brook shoppers were moved to mall basements; more than two-thirds of Homewood residents lost power. Orland Park saw an animal-daycare roof ripped off, and Tinley Park reported shattered windows, flooded streets and inoperable traffic lights. Portage Mayor Austin Bonta declared a local emergency and canceled school for the following day.
Official Statements & Responses
- NWS meteorologist Kevin Donofrio warned winds could reach 70-80 mph and noted the storm’s strength was comparable to a tornado.
- The Federal Aviation Administration issued ground stops at O’Hare (until 11:15 a.m.) and Midway (until 11:30 a.m.).
On-the-Ground Reports
Residents described the event as unprecedented.
Conflicting Reports & Gaps
- Outage totals differ: NY Times cites “nearly a million” customers without power, while Sun-Times provides separate counts for ComEd and NIPSCO.
- Wind measurements vary between a 99 mph gust and reports of up to 110 mph.
- Derecho classification remains provisional; the Storm Prediction Center is still evaluating the event’s criteria, especially for the Cincinnati area.
Verbatim Quotes
- “There are trees down everywhere, from the south Chicago suburbs into northwest Indiana,” — Kevin Donofrio
- “It’s something else. I thought it was a plane crash or a bomb,” — Hector Lopez, resident
What’s Next
Meteorologists expect cooler temperatures and light showers on Wednesday, with the wind threat diminishing as the derecho moves eastward. The NWS will continue tornado surveys in the coming days.
