By Meredith Rodriguez, Peter Nickeas and Lisa Black
Chicago Tribune reporters
10:12 PM CST, February 20, 2014
A storm system with heavy fog is to blame for several tornadoes that touched down in Central Illinois before contributing to a 20-vehicle pileup in Will County and temporarily shutting down Midway International Airport in Chicago.
The fast moving line of thunderstorms caused tornadoes to touch down in four areas in Central Illinois Thursday afternoon between 3 and 5 p.m. before a significantly weaker version hit Chicago during rush hour.
“We have a fast moving line of thunderstorms that originated in Central Missouri this afternoon and raced across from Illinois from West to East,” said Chris Geelhart a meteorologist with the National Weather Service Lincoln office.
The first tornado report came in before 3 p.m. about 50 miles West of Springfield. Reports came in from Mechanicsburg around 4 p.m., then Pana at 4:20 and Shumway before 5 p.m, Geelhart said.
Several buildings were destroyed or damaged in Mechanicsburg, but there were only reports of minor damage like power poles, trees and outbuildings in the other places.
“None of these have been on the ground for a long time,” Geelhart said, “brief touchdowns for the most part.”
He said the snow on the ground in Chicago helped temper the storm here.
“The really strong storms weren’t able to go that far north,” Geelhart said. “It’s looking like it was very weak as it went through Chicago.”
The last batch of storms is moving through Chicago and was to move out by 7:30 p.m., according to the National Weather Service.
“Almost all of the activity is within Cook County now,” said Richard Castro, a meteorologist with the National Weather Service.
While the fog should clear out within the next couple of hours, the fog advisory was expected to end at 7 p.m.
Next, strong, possibly damaging southwest winds will hit this evening until 11 p.m., Castro said.
The storms hit at about 5:30 p.m. and were expected to pass through with south to southwest winds at 30-40 mph, gusting to 60 mph. A high wind warning is in effect until 11 p.m. Temperatures are expected to drop and there could be hail with the rain, according to the National Weather Service.
The dense fog is being blamed this evening with a crash at about 4:40 p.m. that involving 19 vehicles, including seven semi-trucks and 12 passenger vehicles on I-57 northbound in Peotone near Harlem Avenue in Will County, according to Illinois State Police. Officials said 10 people were taken to area hospitals with injuries that were not considered life-threatening.
One of the trucks ignited in flames but did not involve hazordous materials, police said. The interstate was closed from Wilminton-Peotone Road to Manhattan-Monee Road but later reopened.
At about 4:30 p.m., Midway International Airport was in a "ground stop" which meant that no flights were departing. At O'Hare International Airport, some flights were departing but only flights currently in the air were arriving due to the low visibility, officials said.
By 6 p.m., both airports were back up but were experiencing delays of more than 30 minutes, officials said.
O'Hare had 420 flights canceled today while Midway had 185 canceled flights today, officials said.
The rain, combined with the melting snow and ice, has increased the threat of flooding throughout the area. And the standing water will freeze tonight as temperatures reach the 20s.
As much as an inch and a half of rain was expected in some places today. "It's going to be a wait-and-see to see how rivers respond to the heavy rain we're getting this morning," said Gino Izzi, a meteorologist with the weather service.
To prepare for runoff, officials lowered the level by allowing more water out of the Chicago Sanitary and Ship Canal and into the Des Plaines River at Lockport. The amount of rain and snow melt that will become runoff will vary based on how quickly the snow melts and the intensity of the rain.
As of early this afternoon, the Deep Tunnel system's mainstream tunnel was 80 percent full, the Des Plaines tunnel was 50 percent full and the Calumet tunnel was 36 percent full. The entire tunnel and reservoir system can hold up to 2.3 billion gallons. Water is held in the tunnels until it can be treated at water reclamation plants.
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