Best time to fly Fort Myers to Chicago

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

Best month

September

91.6% on time · 168 flights

Worst month

July

68.8% on time · 181 flights

Month Flights On time Cancelled When late, by
January 317 73.6% 2.21% 68 min
February 342 73.6% 1.17% 52 min
March 468 72.5% 4.06% 95 min
April 363 78.5% 1.65% 92 min
May 232 80.1% 0% 67 min
June 178 78.4% 1.12% 81 min
July 181 68.8% 3.31% 58 min
August 179 81.3% 0% 59 min
September 168 91.6% 0% 182 min
October 201 83.6% 0% 106 min
November 266 75.1% 1.88% 110 min
December 337 72.1% 1.78% 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.