Best time to fly San Francisco to San Luis Obispo

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

Best month

August

86.8% on time · 168 flights

Worst month

May

72.9% on time · 204 flights

Month Flights On time Cancelled When late, by
January 179 84.7% 0.56% 108 min
February 162 79% 2.47% 139 min
March 188 80.2% 0.53% 97 min
April 201 79.4% 0% 95 min
May 204 72.9% 0.49% 60 min
June 180 73.4% 0.56% 64 min
July 154 78.6% 0% 111 min
August 168 86.8% 0% 41 min
September 181 84.7% 1.1% 44 min
October 244 80.5% 0% 66 min
November 234 75.7% 4.7% 121 min
December 180 72.9% 3.33% 174 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.