Best time to fly Chicago to Oklahoma City

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

Best month

September

81.7% on time · 389 flights

Worst month

July

64.9% on time · 407 flights

Month Flights On time Cancelled When late, by
January 334 70.3% 3.29% 83 min
February 319 74.2% 2.51% 75 min
March 402 71.1% 3.23% 93 min
April 418 77.5% 3.59% 51 min
May 462 77.5% 0.43% 71 min
June 465 65.6% 2.15% 92 min
July 407 64.9% 0.49% 77 min
August 396 74.5% 1.77% 66 min
September 389 81.7% 0.51% 62 min
October 447 74.9% 0.22% 73 min
November 406 71.9% 3.2% 65 min
December 380 68.6% 1.84% 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.