Best time to fly Chicago to Fort Myers

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

Best month

September

91.7% on time · 169 flights

Worst month

March

67.4% on time · 469 flights

Month Flights On time Cancelled When late, by
January 318 70.6% 1.89% 70 min
February 343 80.7% 1.46% 65 min
March 469 67.4% 4.26% 74 min
April 364 73.6% 1.92% 66 min
May 232 81.5% 0% 80 min
June 177 81.1% 1.13% 59 min
July 182 75.7% 2.2% 67 min
August 180 77.8% 0% 65 min
September 169 91.7% 0% 54 min
October 201 83.9% 0% 58 min
November 266 79.6% 2.26% 76 min
December 338 68.6% 0.89% 77 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.