Best time to fly Denver to New York

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

Best month

April

87.6% on time · 209 flights

Worst month

July

65.5% on time · 308 flights

Month Flights On time Cancelled When late, by
January 220 78.4% 2.73% 61 min
February 195 80.2% 6.67% 81 min
March 258 81.8% 0.78% 96 min
April 209 87.6% 0% 53 min
May 248 81.7% 0.81% 52 min
June 280 71.4% 1.79% 100 min
July 308 65.5% 6.49% 96 min
August 289 75.1% 3.46% 87 min
September 260 85.3% 0.38% 90 min
October 296 85.7% 0.68% 88 min
November 262 82% 0.38% 94 min
December 301 77.4% 2.66% 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.