Best time to fly Jacksonville to Philadelphia

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

Best month

April

89% on time · 137 flights

Worst month

July

54.6% on time · 142 flights

Month Flights On time Cancelled When late, by
January 115 86% 6.96% 94 min
February 102 81.1% 6.86% 134 min
March 115 81.8% 4.35% 76 min
April 137 89% 0.73% 72 min
May 151 82.6% 1.32% 175 min
June 162 73.9% 3.09% 91 min
July 142 54.6% 8.45% 114 min
August 146 68.3% 2.74% 97 min
September 117 85.5% 0% 53 min
October 135 79.7% 1.48% 74 min
November 112 88.2% 1.79% 105 min
December 119 76.7% 2.52% 89 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.