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 IAD record →

There is not yet enough of the year on record for this route to say anything about seasons. The months below are shown as recorded.

Month Flights On time Cancelled When late, by
January 18 75% 11.11% 134 min
February 21 76.2% 0% 80 min
March 29 82.8% 0% 94 min
June 1 100% 0%
July 30 89.3% 6.67% 138 min
August 31 96.8% 0% 51 min
September 1 100% 0%
October 6 83.3% 0% 50 min
November 30 86.2% 3.33% 47 min
December 17 64.7% 0% 36 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.