Best time to fly Atlanta to Louisville

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

Best month

September

93.7% on time · 222 flights

Worst month

March

78.6% on time · 231 flights

Month Flights On time Cancelled When late, by
January 191 84.8% 3.66% 50 min
February 195 85.1% 0.51% 41 min
March 231 78.6% 4.76% 59 min
April 240 89.5% 1.25% 41 min
May 263 83.8% 1.52% 68 min
June 236 87.6% 0.42% 62 min
July 230 78.9% 0.87% 78 min
August 241 84.8% 0.41% 56 min
September 222 93.7% 0% 34 min
October 229 89.5% 0% 52 min
November 214 81.4% 1.87% 103 min
December 215 80.3% 3.26% 79 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.