Best time to fly New York to Phoenix

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

Best month

April

85.9% on time · 278 flights

Worst month

December

63.6% on time · 270 flights

Month Flights On time Cancelled When late, by
January 276 79% 6.88% 85 min
February 248 79.9% 7.66% 59 min
March 289 81.6% 2.08% 57 min
April 278 85.9% 0% 98 min
May 269 80.8% 1.49% 78 min
June 257 74.2% 0.39% 61 min
July 203 72.6% 2.96% 98 min
August 203 85.5% 1.48% 46 min
September 197 79.4% 0.51% 89 min
October 235 75.2% 1.7% 65 min
November 247 76.9% 1.62% 81 min
December 270 63.6% 4.44% 79 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.