Best time to fly San Francisco to Kalispell

Every month pooled across the years on record, so "July" means July generally rather than one particular July. Full SFO to FCA 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 28 76.9% 3.57% 24 min
February 24 87.5% 0% 19 min
March 29 89.7% 0% 33 min
April 2 100% 0%
May 21 55% 4.76% 50 min
June 64 70.3% 0% 41 min
July 78 79.5% 0% 45 min
August 78 79.5% 0% 47 min
September 61 80.3% 0% 48 min
October 25 80% 0% 39 min
December 18 77.8% 0% 74 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.