Best time to fly Atlanta to Washington

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

Best month

October

82.3% on time · 1,173 flights

Worst month

July

59.6% on time · 1,173 flights

Month Flights On time Cancelled When late, by
January 1,164 73% 8.93% 71 min
February 1,059 61.6% 2.64% 60 min
March 1,171 66% 2.99% 62 min
April 1,143 71.6% 0.87% 58 min
May 1,166 68% 1.63% 68 min
June 1,129 66.1% 4.52% 93 min
July 1,173 59.6% 7.16% 99 min
August 1,147 74.4% 1.66% 80 min
September 1,151 81.6% 0.43% 65 min
October 1,173 82.3% 0.09% 49 min
November 1,110 77.2% 1.62% 73 min
December 1,117 69.1% 1.97% 61 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.