Best time to fly Birmingham to Washington

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

Best month

August

88% on time · 86 flights

Worst month

February

67.9% on time · 80 flights

Month Flights On time Cancelled When late, by
January 89 74.4% 12.36% 78 min
February 80 67.9% 2.5% 76 min
March 88 76.3% 9.09% 121 min
April 85 77.1% 2.35% 172 min
May 88 79.3% 1.14% 68 min
June 86 72.4% 11.63% 149 min
July 88 74.7% 13.64% 70 min
August 86 88% 3.49% 232 min
September 86 74.1% 0% 57 min
October 91 82.4% 0% 54 min
November 88 77% 1.14% 103 min
December 89 72.1% 3.37% 110 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.