Best time to fly Sun Valley/Hailey/Ketchum to San Francisco

Every month pooled across the years on record, so "July" means July generally rather than one particular July. Full SUN 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 42 81% 0% 97 min
February 37 78.4% 0% 62 min
March 40 92.5% 0% 34 min
April 7 71.4% 0% 29 min
May 9 33.3% 0% 29 min
June 31 3.2% 0% 55 min
July 34 38.2% 0% 68 min
August 34 79.4% 0% 78 min
September 14 78.6% 0% 45 min
October 11 72.7% 0% 112 min
December 33 57.6% 0% 141 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.