Early October in Chicago usually means nice, cool weather for runners in the 2007 LaSalle Bank Chicago Marathon, but not this year.

Weather forecasters are predicting the hottest LaSalle Bank Chicago Marathon on record, with temperatures expected to reach 88 degrees--nearly 30 degrees higher than the average temperature for the last 10 editions of the race.

Besides throwing a monkey wrench into the predicted times of the thousands of casual runners, the hot, humid weather will be a wild card for the elite runners. The 3007 LaSalle Bank Chicago Marathon is the second-to-last leg of the 2006-2007 World Marathon Majors, a series of five top international marathons that award points for cumulative results in the series, similar to the tennis Grand Slam Cup.

Some runners handle the heat much better than others, so the winners on Sunday may not be the fastest pure marathoners in the race, but the ones that can pace themselves and deal with the conditions the best.