Best time to fly Newark to Key West

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

Best month

June

90% on time · 60 flights

Worst month

December

68.5% on time · 75 flights

Month Flights On time Cancelled When late, by
January 67 75.4% 2.99% 67 min
February 73 85.3% 6.85% 67 min
March 93 76.9% 1.08% 72 min
April 89 82% 0% 68 min
May 62 75.4% 1.61% 82 min
June 60 90% 0% 87 min
July 62 73.8% 1.61% 107 min
August 62 86.2% 4.84% 49 min
September 60 87.9% 3.33% 53 min
October 62 76.3% 4.84% 46 min
November 60 78.3% 0% 111 min
December 75 68.5% 1.33% 68 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.