Best time to fly Atlanta to Houston

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

Best month

September

86.2% on time · 384 flights

Worst month

July

64.9% on time · 414 flights

Month Flights On time Cancelled When late, by
January 394 78% 4.31% 72 min
February 384 85.9% 0.26% 64 min
March 439 74.9% 6.38% 85 min
April 469 80.5% 0.43% 56 min
May 444 68.9% 0.45% 64 min
June 396 71.6% 1.77% 63 min
July 414 64.9% 2.17% 73 min
August 380 72.9% 1.05% 65 min
September 384 86.2% 0.26% 58 min
October 439 78.9% 0.46% 61 min
November 402 81.7% 1.99% 75 min
December 369 73.1% 2.98% 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.