Best time to fly Des Moines to Dallas/Fort Worth

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

Best month

May

82.1% on time · 123 flights

Worst month

July

60.7% on time · 118 flights

Month Flights On time Cancelled When late, by
January 123 76.6% 13.01% 113 min
February 113 77% 0% 140 min
March 123 80.3% 3.25% 107 min
April 121 81.2% 2.48% 56 min
May 123 82.1% 4.88% 93 min
June 119 62.5% 5.88% 121 min
July 118 60.7% 5.08% 100 min
August 118 72.8% 2.54% 95 min
September 119 71.9% 2.52% 68 min
October 121 72.9% 2.48% 78 min
November 116 67% 5.17% 137 min
December 122 64.7% 1.64% 85 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.