Best time to fly Kansas City to Chicago

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

Best month

September

85.1% on time · 573 flights

Worst month

July

70.1% on time · 643 flights

Month Flights On time Cancelled When late, by
January 540 78.4% 4.81% 100 min
February 580 80.6% 0.69% 86 min
March 660 75.8% 4.7% 106 min
April 736 78.4% 2.17% 106 min
May 771 82.5% 0.91% 95 min
June 720 75% 2.64% 114 min
July 643 70.1% 3.73% 76 min
August 596 77.6% 1.01% 96 min
September 573 85.1% 0.17% 45 min
October 672 82.4% 0% 61 min
November 650 83% 3.08% 89 min
December 569 75.2% 1.23% 92 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.