Highest temperature in Chicago on September 17? - 73 or below

Prediction market on polymarket_us. Will the highest temperature recorded at Chicago Midway Airport (KMDW) in Chicago for 2026-09-17 as reported by the National Weather Service's Climatological Report (Daily) be less than or equal to 73F? Outcome verified from NWS Climatological Report.

Resolves: 9/18/2026.