Best time to fly Fresno to San Francisco

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

Best month

March

82.1% on time · 95 flights

Worst month

April

50.9% on time · 110 flights

Month Flights On time Cancelled When late, by
January 92 70.5% 4.35% 91 min
February 83 66.3% 0% 93 min
March 95 82.1% 0% 81 min
April 110 50.9% 1.82% 70 min
May 108 55.6% 0% 94 min
June 90 53.3% 0% 67 min
July 119 73.9% 0% 82 min
August 116 77.6% 0% 96 min
September 118 68.6% 0% 80 min
October 144 63.9% 0% 57 min
November 119 69.6% 5.88% 93 min
December 82 73.1% 3.66% 81 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.