Best time to fly Houston to Cincinnati

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

Best month

January

90% on time · 84 flights

Worst month

July

55.6% on time · 78 flights

Month Flights On time Cancelled When late, by
January 84 90% 4.76% 59 min
February 79 82.3% 0% 55 min
March 93 67% 2.15% 65 min
April 90 75.6% 0% 64 min
May 130 77.3% 1.54% 76 min
June 120 68.9% 0% 73 min
July 78 55.6% 7.69% 78 min
August 112 69.1% 1.79% 63 min
September 133 73.7% 0% 55 min
October 126 80.2% 0% 47 min
November 113 75.2% 0% 60 min
December 80 61.5% 2.5% 50 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.