Updated 04/19/11 – 8:51 p.m.
CHICAGO (CBS/STMW) —Hail is falling across the Chicagoland area with thunderstorms producing torrential rainfall that could cause some flooding Tuesday night.
The National Weather Service has issued a flood advisory for central and northern Cook County, DuPage and northwestern Will County in effect until midnight.
More than 450 flights have been canceled at O’Hare Airport as hail and torrential rainfall hit the Chicago area Tuesday night.
Because of continuing rain and low visibility in the area, flights in and out of O’Hare were averaging 90 minutes delays as of 8:30 p.m., while airlines had canceled more than 450 flights for the day, the city’s Department of Aviation said.
At Midway, there were some delays of 30 minutes and minor cancellations, the department said.
At 8 p.m. the NWS Doppler Radar found thunderstorms producing torrential rainfall. The radar and spotters estimate that these storms are producing more than an inch of rain less than an hour.
Runoff from that water will cause urban and small streams across the greater Chicago area, the weather service said.
In Saint Charles, 0.99 inches of rain was measured in less than 20 minutes. And in Schaumburg, a trainer spotter recorded .88 of an inch of hail. Dime-sized hail was also spotted in Naperville near Hobson Road.
The heavy rainfall will cease about 11 p.m., but there’s still a chance of rain between 11 p.m. and 1 a.m. Wednesday.
And on Wednesday, the Chicago area will be left with the cold, but no rain. The high will hit 45 degrees, while the low will be a chilly 32 degrees.
CBS 2 Meteorologist Megan Glaros says early Tuesday morning, more snow was seen in southern Wisconsin, southern Minnesota and northern Iowa, and some parts of McHenry County saw a dusting overnight.
Storms now over Missouri and downstate Illinois have prompted a severe thunderstorm watch. The storm system will work its way northeast, and will sweep just south of the Chicago area.
Areas to the south, including Kankakee, Peru, and areas of Indiana south of Crown Point, are at a moderate risk for severe weather.
Whatever the case, Chicagoans are likely to find an invigorating spring storm preferable to the weather on Monday morning, which brought a record snowfall for the date.
Glaros said at O’Hare International Airport Monday morning, total snow accumulation amounted to 0.6 inches, but even that was enough to set a record for this date. It swept out an earlier record of 0.4 inches, set in 1910.
Some areas of McHenry County saw nearly 2 1/2 inches of snow, while residents in some of the north and western suburbs reported 1-2 inches of snow. Some north suburban areas saw in excess of 3 inches of snow.
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