Best time to fly Los Angeles to Chicago

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

Best month

February

83.4% on time · 453 flights

Worst month

March

69.4% on time · 549 flights

Month Flights On time Cancelled When late, by
January 463 77.3% 1.73% 69 min
February 453 83.4% 0% 66 min
March 549 69.4% 3.1% 97 min
April 552 78.8% 1.27% 82 min
May 601 77.7% 0.67% 87 min
June 659 73.6% 1.82% 96 min
July 688 77.2% 3.63% 90 min
August 668 73.4% 1.95% 88 min
September 614 81.8% 0.16% 69 min
October 564 80.8% 0.18% 67 min
November 584 71.3% 3.77% 86 min
December 569 73.5% 1.23% 107 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.