Best time to fly Denver to Casper

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

Best month

October

87.7% on time · 402 flights

Worst month

June

62.4% on time · 445 flights

Month Flights On time Cancelled When late, by
January 403 73.7% 1.24% 89 min
February 362 76% 0.83% 74 min
March 401 80.9% 2% 68 min
April 389 78% 1.8% 71 min
May 423 75.2% 0.95% 67 min
June 445 62.4% 0.45% 82 min
July 425 74.2% 1.18% 80 min
August 417 70.4% 1.2% 95 min
September 389 83.2% 0% 56 min
October 402 87.7% 0.5% 56 min
November 383 85.3% 2.35% 76 min
December 403 81.8% 0.25% 92 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.