Best time to fly Pittsburgh to San Francisco

Every month pooled across the years on record, so "July" means July generally rather than one particular July. Full PIT to SFO 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 36 80% 2.78% 117 min
February 28 71.4% 0% 62 min
March 33 96.9% 3.03% 24 min
April 43 72.1% 0% 50 min
May 57 71.4% 0% 55 min
June 55 67.3% 0% 73 min
July 57 82.5% 0% 71 min
August 54 85.2% 0% 37 min
September 51 94.1% 0% 29 min
October 49 93.8% 0% 37 min
November 49 91.8% 0% 52 min
December 44 72.1% 2.27% 86 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.