Best time to fly Columbia to Washington

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

Best month

September

80.5% on time · 196 flights

Worst month

February

53.8% on time · 160 flights

Month Flights On time Cancelled When late, by
January 176 67.8% 13.07% 116 min
February 160 53.8% 8.75% 82 min
March 177 75% 9.6% 109 min
April 175 73.1% 2.29% 98 min
May 179 77.3% 3.91% 65 min
June 171 75% 11.11% 165 min
July 172 67.6% 13.95% 90 min
August 174 71.3% 5.17% 91 min
September 196 80.5% 2.04% 61 min
October 204 78.4% 0% 47 min
November 188 68.5% 2.66% 81 min
December 172 58% 1.16% 76 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.