Best time to fly Rochester to Washington

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

Best month

October

89.4% on time · 180 flights

Worst month

February

50.3% on time · 184 flights

Month Flights On time Cancelled When late, by
January 196 72% 9.69% 110 min
February 184 50.3% 9.78% 76 min
March 200 64.5% 6% 98 min
April 205 70.8% 1.46% 91 min
May 210 71.8% 3.33% 110 min
June 190 71.9% 10% 139 min
July 177 73.6% 7.34% 121 min
August 180 71.6% 2.22% 109 min
September 176 83.4% 0.57% 55 min
October 180 89.4% 0% 57 min
November 166 72.8% 2.41% 61 min
December 164 64.8% 1.22% 137 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.