Best time to fly Charlotte to San Francisco

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

Best month

March

82.9% on time · 118 flights

Worst month

June

34.8% on time · 140 flights

Month Flights On time Cancelled When late, by
January 95 73.2% 13.68% 43 min
February 97 79.2% 1.03% 50 min
March 118 82.9% 0.85% 70 min
April 133 58.6% 0% 47 min
May 143 54.5% 0% 51 min
June 140 34.8% 1.43% 55 min
July 140 55.5% 0.71% 60 min
August 131 60.8% 0.76% 51 min
September 137 77.4% 0% 60 min
October 148 77% 0% 69 min
November 103 80.6% 0% 57 min
December 111 66.7% 0% 67 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.