Best time to fly Washington to Birmingham

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

Best month

November

82.4% on time · 170 flights

Worst month

February

57.7% on time · 150 flights

Month Flights On time Cancelled When late, by
January 150 67.4% 14% 82 min
February 150 57.7% 8.67% 91 min
March 176 70.6% 6.25% 82 min
April 172 71.9% 2.33% 77 min
May 176 69.6% 2.27% 76 min
June 172 64.3% 9.88% 73 min
July 172 63% 10.47% 88 min
August 171 74.4% 4.09% 111 min
September 171 80.5% 1.17% 98 min
October 181 80.1% 0% 66 min
November 170 82.4% 0% 99 min
December 171 67.5% 2.92% 87 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.