CHICAGO (CBS) -- Race officials with the Bank of America Chicago Marathon were taking a wait-and-see approach to the potential for temperatures that will be warmer than ideal for runners on Sunday.
With temperatures expected to reach the middle or upper70s, marathon organizers said they're keeping an eye on things.
"We've seen warmer weather, so it's something we've adapted to," said race director Carey Pinkowski. "We're talking with our volunteers, with our medical team, with everyone involved with our city agencies. So we'll make the adjustments. We'll make our final call tomorrow morning, and get ready for what the weather brings on race day."
Approximately 45,000 runners have registered for the marathon. Pinkowski said in such warm weather, runners shouldn't try to set any records.
"The messaging that we send out to our participants is important. Obviously, Sunday may not be the day to set a personal best, or qualify for the Boston Marathon, so it's something that our participants will be keenly aware of," he said.
The normal high temperature for Oct. 11 in Chicago is 64 degrees, according to the National Weather Service, and it's often said the ideal temperature for a marathon is about 50 degrees. As of Thursday afternoon, forecasters were expecting a high of about 75 on Sunday.
That's still nowhere close to the high of 87 during the 2007 marathon, a record high for that date. Organizers were forced to cancel the 2007 marathon mid-race, after many runners were overcome by the heat. More than 300 people were picked up by ambulances along the race course, and one runner died of a previously undiagnosed heart valve condition.
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