Chicago Marathon Weather

It will be chilly for the 2012 Chicago Marathon. Early morning temperatures for the start of the race will be from 33-38 degrees. The warmest will be along the lake front. By early afternoon temperatures will have climbed to around 50. Early morning winds will be northwest 4-8 mph, highest near the lake. By early afternoon the winds will be northwest 10-15 mph. Skies will be mostly sunny to add a warming feel if you are in the sunshine. That is where you want to be if you are a spectator.

The graphic from the Chicago Tribune gives a pretty good picture of conditions during the race. Interesting to note how warm 4 of the recent 5 events have been. Of course, the worst conditions were those in 2007. What made those conditions so bad was not the heat itself, but the moisture (dew point) level of the air. The higher the dew point, the higher the moisture, and the less the body can be cooled down as the perspiration does not evaporate. It is the evaporative process that produces the cooling. Moist days feel sticky because your skin moisture is not evaporating as quickly as on dry air days.

http://www.examiner.com/article/chicago-marathon-weather