Best time to fly Charleston to Philadelphia

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

Best month

February

88.1% on time · 45 flights

Worst month

July

69.7% on time · 104 flights

Month Flights On time Cancelled When late, by
January 44 77.5% 9.09% 108 min
February 45 88.1% 6.67% 100 min
March 78 80.5% 1.28% 191 min
April 91 81.3% 0% 34 min
May 100 80.8% 1% 97 min
June 91 80.2% 5.49% 51 min
July 104 69.7% 3.85% 98 min
August 126 82.9% 2.38% 99 min
September 109 80.7% 0% 55 min
October 125 76.8% 0% 71 min
November 111 77.5% 0% 102 min
December 85 73.8% 1.18% 145 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.