Best time to fly Aspen to Houston

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

Best month

May

100% on time · 20 flights

Worst month

April

44.2% on time · 43 flights

Month Flights On time Cancelled When late, by
January 189 69.5% 7.94% 90 min
February 160 73.8% 8.75% 115 min
March 205 71.5% 8.78% 101 min
April 43 44.2% 0% 62 min
May 20 100% 0%
June 94 57% 4.26% 132 min
July 122 64.3% 7.38% 106 min
August 102 60.6% 0.98% 86 min
September 67 72.7% 0% 114 min
October 52 80.8% 0% 83 min
November 30 70.4% 10% 71 min
December 138 57.8% 7.25% 109 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.