Best time to fly Jacksonville to Denver

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

Best month

November

96.7% on time · 91 flights

Worst month

June

60% on time · 85 flights

Month Flights On time Cancelled When late, by
January 88 93.2% 0% 65 min
February 77 80.3% 1.3% 105 min
March 95 78.7% 1.05% 68 min
April 91 86.8% 0% 75 min
May 91 80.9% 0% 67 min
June 85 60% 0% 64 min
July 62 87.1% 0% 138 min
August 62 91.8% 0% 40 min
September 66 81.8% 0% 36 min
October 92 87% 0% 93 min
November 91 96.7% 0% 23 min
December 95 81.1% 0% 57 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.