Best time to fly Birmingham to Denver

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

Best month

February

94% on time · 84 flights

Worst month

June

69.8% on time · 116 flights

Month Flights On time Cancelled When late, by
January 93 91.4% 0% 48 min
February 84 94% 0% 73 min
March 116 80.7% 1.72% 94 min
April 116 82.8% 0% 59 min
May 118 84.7% 0% 60 min
June 116 69.8% 0% 44 min
July 93 76.9% 0% 60 min
August 93 75.8% 0% 74 min
September 89 85.4% 0% 97 min
October 93 87.1% 0% 39 min
November 88 92% 0% 45 min
December 93 82.8% 0% 71 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.