Best time to fly Chicago to Minneapolis

Every month pooled across the years on record, so "July" means July generally rather than one particular July. Full MDW to MSP record →

Best month

October

87.8% on time · 246 flights

Worst month

December

61.8% on time · 214 flights

Month Flights On time Cancelled When late, by
January 186 73.7% 0% 80 min
February 180 87.2% 0.56% 68 min
March 225 68.9% 5.78% 74 min
April 220 82.9% 1.82% 67 min
May 149 83.8% 0.67% 56 min
June 132 64.1% 2.27% 45 min
July 249 69.4% 0.4% 69 min
August 237 74.2% 0.42% 64 min
September 232 80.6% 0% 46 min
October 246 87.8% 0% 46 min
November 215 86.5% 6.98% 91 min
December 214 61.8% 0.93% 72 min

What a seasonal pattern can and cannot tell you

Months differ for reasons that repeat — summer thunderstorms in the American interior, winter fog and de-icing in northern Europe, school holidays filling every seat and leaving no slack in the schedule. Those are real and they come back each year.

What the pattern cannot do is forecast a particular flight. A quiet month has late days and a bad month has punctual ones. Treat this as a way to choose between two dates you are indifferent about, not as a promise.