Best time to fly Newark to Detroit

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

Best month

September

84.8% on time · 683 flights

Worst month

July

67.1% on time · 646 flights

Month Flights On time Cancelled When late, by
January 498 79.4% 5.22% 71 min
February 487 83.7% 6.57% 77 min
March 551 83.3% 2.9% 78 min
April 483 83.3% 0.62% 80 min
May 451 78.8% 3.77% 122 min
June 529 75.7% 3.59% 136 min
July 646 67.1% 8.98% 102 min
August 663 77.4% 5.13% 108 min
September 683 84.8% 1.02% 96 min
October 664 77.4% 0.6% 60 min
November 591 78.3% 4.74% 86 min
December 531 68.2% 3.39% 75 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.