Best time to fly Minneapolis to San Francisco

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

Best month

September

89.2% on time · 157 flights

Worst month

May

43% on time · 169 flights

Month Flights On time Cancelled When late, by
January 142 76.6% 0.7% 73 min
February 129 73.6% 0% 57 min
March 142 83.2% 3.52% 46 min
April 166 63.9% 0% 57 min
May 169 43% 1.18% 57 min
June 183 44.8% 0% 46 min
July 193 75.1% 0% 58 min
August 181 81.8% 0% 54 min
September 157 89.2% 0% 64 min
October 170 78.2% 0% 46 min
November 148 81% 0.68% 66 min
December 139 59.7% 2.88% 79 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.