2 min readIt’s that time of year again. While the fall marathoning season can bring PR-worthy conditions, there’s always the threat of a random cold front moving in or August rearing its head.
But if you’re running at Sunday’s Chicago Marathon, you’re in for a treat. The forecast looks near-perfect, with temperatures in the high 40s and low 50s on race morning with some cloud coverage and mild wind. The humidity is predicted to be in the 50 to 70 percent range, and no rain is expected.
Some of you might be breathing a sigh of relief. The first week of October has been unseasonably warm in the Windy City so far, with daily highs in the low 80s early in the week, until dropping down to the 60s on Thursday. Luckily, the weekend has brought back cooler conditions.
Here’s a quick look at the forecast for Sunday, according to Weather Underground.
Time | Temp. (F) | Feels Like | Wind |
5:00 a.m. | 46° | 43° | 7 mph W |
7:00 a.m. | 47° | 43° | 7 mph WNW |
9:00 a.m. | 49° | 45° | 8 mph WNW |
11:00 a.m. | 52° | 49° | 9 mph WNW |
1:00 p.m. | 53° | 51° | 9 mph WNW |
3:00 p.m. | 54° | 52° | 9 mph NW |
For a bit of historical context, the 2019 Chicago Marathon—which saw Brigid Kosgei set the (now broken) women’s world record of 2:14:04—had great weather. Temperatures were in the low to mid 40s in the morning before peaking at 55 degrees at 2 p.m. Last year’s race was a bit warmer, with temperatures in the high 40s early in the morning before rising as high as 71 degrees in the mid-afternoon. According to the National Weather Service, October 8 in Chicago has historically had an average temperature of 57 degrees.
Just a few weeks ago at the Berlin Marathon, Tigst Assefa took down Kosgei’s world record by over two minutes, partially thanks to marathon-friendly weather. Conditions were in the high 50s with some cloud coverage.
If you’ve been keeping up with running news, you know that poor marathon weather can drastically impact a race. Last weekend’s Twin Cities Marathon and 10 Mile in Minnesota was canceled at the last minute because of warm conditions that were considered potentially dangerous to participants. And back in May, the Flying Pig Marathon in Cincinnati, Ohio, faced criticism after telling runners to “shelter-in-place” during the race after strong thunderstorms rolled in.
But so far, it looks like smooth sailing for Sunday in Chicago.
Need some help choosing your race day outfit? Check out our What to Wear tool. Just enter the weather conditions, and it will provide you with some suggestions to dress accordingly.
Theo Kahler is the news editor at Runner’s World. He’s a former all-conference collegiate runner at Winthrop University, and he received his master’s degree in liberal arts studies from Wake Forest University, where he was a member of one of the top distance-running teams in the NCAA. Kahler has reported on the ground at major events such as the Paris Olympics, U.S. Olympic Trials, New York City Marathon, and Boston Marathon. He’s run 14:20 in the 5K, 1:05:36 in the half marathon, and enjoys spotting tracks from the sky on airplanes. (Look for colorful ovals around football fields.)
