Best time to fly Dallas to Denver

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

Best month

January

82.5% on time · 249 flights

Worst month

May

58.6% on time · 257 flights

Month Flights On time Cancelled When late, by
January 249 82.5% 3.61% 46 min
February 234 78.4% 0.85% 55 min
March 270 72.1% 0.37% 70 min
April 254 71.5% 0.39% 61 min
May 257 58.6% 1.95% 55 min
June 263 58.6% 2.28% 56 min
July 289 63.3% 1.73% 66 min
August 237 63.4% 0% 54 min
September 223 69.1% 0% 51 min
October 237 69.5% 0.42% 55 min
November 234 74.3% 5.13% 60 min
December 255 70.6% 0% 57 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.