The National Weather Service issued a tornado warning for southern DuPage County on Tuesday, Aug. 11, placing Downers Grove, Woodridge and Westmont directly in the path of severe thunderstorms capable of producing tornadoes and straight-line wind damage.
The warning, issued at 10:10 a.m., was based on radar-indicated rotation in storms moving east at 55 mph from near Yorkville. Four minutes later, the NWS Chicago confirmed on Facebook that the Aurora Airport in Sugar Grove had recorded an 85 mph gust, exceeding the forecast maximum.
By 10:33 a.m., the NWS expanded the tornado warning to include central and northern DuPage County, eastward across Cook County and into Chicago.
The NWS warned that heavy rainfall could mask an approaching tornado and urged residents to take cover immediately, moving to an interior room on the lowest floor of a building.
Sirens sounded, power lost
A Downers Grove resident reported on the NWS Chicago Facebook page that tornado sirens sounded three times within an hour in the area west of Belmont Avenue. Paul Geralds noted electricity went out around 11:03 a.m.
A resident commented on the same page as the expanded warning was issued:
"Downers Grove hit hard and fast, anyone in the way of this, take it seriously."
Flood advisory covers DuPage County
The NWS also issued a flood advisory for DuPage County, in effect until 1:30 p.m., after Doppler radar and automated rain gauges detected rainfall rates of 2 to 3 inches per hour. The agency warned of flooding on roads, in low-lying areas and in basements.
A severe thunderstorm watch remained in effect until 2 p.m. Tuesday for the broader Chicago area.
More storms expected through the week
The NWS Hazardous Weather Outlook issued early Tuesday morning rated the day's damaging wind risk at Level 3 of 5, with gusts up to 80 mph, and tornado risk at Level 1 of 5. The outlook warned of an active storm pattern persisting through Friday, with additional rounds of thunderstorms and flash flooding possible.
Wednesday carries a 40% chance of storms, mainly between noon and 4 p.m. Thursday's chance rises to 50%.
What residents should do
The NWS tornado warning directed residents to shelter in place during active warnings, stay away from windows and avoid flooded roadways. Floodwater stranded a vehicle on a Woodridge street during storms earlier in the week.
No confirmed damage reports or injuries from Downers Grove, Woodridge or Westmont had been verified as of publication. Local police and fire departments had not issued public statements on the storm's impact at the time of this report.
Residents can report downed trees, power outages or flooding to their local non-emergency police lines or call 911 for life-threatening emergencies.
