Best time to fly Charleston/Dunbar to Chicago

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

Best month

April

77.9% on time · 181 flights

Worst month

December

57.7% on time · 133 flights

Month Flights On time Cancelled When late, by
January 127 60% 7.87% 92 min
February 111 60.9% 0.9% 142 min
March 150 61.2% 6% 80 min
April 181 77.9% 3.87% 82 min
May 197 75.3% 0.51% 99 min
June 177 68% 1.13% 96 min
July 172 65.3% 0.58% 118 min
August 176 63.4% 1.7% 91 min
September 177 71.8% 0% 93 min
October 180 76.1% 0% 93 min
November 150 68.1% 5.33% 82 min
December 133 57.7% 1.5% 109 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.