May 31, 2018 8:58 am May 2018 Becomes Wettest on Record for Chicago Wednesday’s rainfall lifted the month of May to the wettest on record in Chicago. Kalee Dionne reports. Local 1:44 CHICAGO FORECAST: Storms impact region ahead of weekend cooldown 2:25 Thursday afternoon forecast 3:05 Thursday morning weather 2:16 Wednesday afternoon forecast 3:03 Wednesday morning weather