CHICAGO (STMW) — Several Chicago-area counties are under a flash flood warning and roughly 21,000 people are without power Tuesday night after “torrential” thunderstorms moved across the metro area.

The storms brought 60 mph wind gusts and hailstones, along with the “torrential” 1 to 2-inch downpours within an hour or less, National Weather Service said.

As of about 9:30 p.m., the line of thunderstorms had reached Beverly Shores, Ind., after blasting its way through the southwestern suburbs and into Chicago, where roughly 21,000 ComEd customers are without power.

Hardest hit are the southern suburbs, were 10,500 ComEd customers are without power, spokeswoman Krissy Posey said. About 9,000 people in Chicago are in the dark, and 1,100 people in the northern metro area are without electricity. Roughly 220 west suburban homes are without power.

Viaducts throughout the city are flooded, and crews are responding to downed and arcing powerlines, according to Chicago Fire Department officials. No one has been reported injured.

Midway Airport, on the city’s Southwest Side, saw 1.96 inches of rain in about an hour and fifteen minute span, NWS Meterologist Mike Bardou said.

In the southwest suburbs, Bolingbrook saw 1.46 inches of rain, most of which fell in just 45 minutes. Romeoville, where the weather service is headquartered, saw an inch of rain while Frankfort saw about 0.8 inches.

The downpour left three-quarters of an inch of rain in south suburban Tinley Park in about 40 minutes, while west suburban Woodridge was soaked with 1.35 inches of rain as of Tuesday night.

Northwestern Will County, southern and central Cook County and southern DuPage County are under a flash flood warning until 2:30 a.m. because of the “excessive” storm runoff. Most of the rest of the Chicago area is still under a flash flood watch Tuesday night.

A severe thunderstorm watch is in effect for most of northwest Indiana until 2 a.m.

Forecasters earlier issued a tornado warning for west-central Will County and east-central Grundy County after spotting a thunderstorm with rotating winds near Elwood, but that warning was called off about 9 p.m.

However, strong winds uprooted large trees near Coal City, and blew the roof off of a machine shed near Marseilles in LaSalle County, Bardou said. Forecasters could not say Tuesday night whether a tornado caused that damage.

Closer to the Chicago area, residents could see another round of showers and thunderstorms overnight, most likely south of Interstate 88 and Interstate 90, Bardou said.

Lows overnight drop into the upper 60s. Wednesday will be partly sunny with highs in the mid-80s, with more rain likely in the morning, and possible again in the afternoon, forecasters said.

(Source: Sun-Times Media Wire © Chicago Sun-Times 2013. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

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