Best time to fly Charlotte to Chicago

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

Best month

September

84.8% on time · 125 flights

Worst month

July

64.6% on time · 164 flights

Month Flights On time Cancelled When late, by
January 76 76.4% 2.63% 41 min
February 83 81.7% 1.2% 85 min
March 115 76.6% 1.74% 51 min
April 116 81.4% 0.86% 48 min
May 119 71.2% 0.84% 58 min
June 157 69.5% 1.27% 71 min
July 164 64.6% 1.22% 65 min
August 131 71.3% 1.53% 50 min
September 125 84.8% 0% 47 min
October 140 81.4% 0% 41 min
November 115 77.7% 2.61% 42 min
December 121 66.7% 0.83% 59 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.