Best time to fly Houston to San Diego

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

Best month

February

87.1% on time · 249 flights

Worst month

July

64.1% on time · 326 flights

Month Flights On time Cancelled When late, by
January 257 85.1% 2.33% 54 min
February 249 87.1% 0% 59 min
March 294 86.3% 0.68% 85 min
April 283 82.3% 0% 39 min
May 294 76.3% 1.02% 68 min
June 283 66% 0.35% 68 min
July 326 64.1% 5.21% 93 min
August 322 81.3% 0.31% 56 min
September 280 87.1% 0.36% 49 min
October 294 81.3% 0.68% 43 min
November 290 84.5% 0% 52 min
December 293 80.1% 0.68% 84 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.