Best time to fly Seattle to Atlanta

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

Best month

February

91.1% on time · 191 flights

Worst month

July

69.3% on time · 347 flights

Month Flights On time Cancelled When late, by
January 213 86.3% 0.94% 71 min
February 191 91.1% 0.52% 63 min
March 231 80.8% 1.3% 63 min
April 251 85.5% 0.8% 48 min
May 298 82.8% 0% 97 min
June 325 83.6% 0% 97 min
July 347 69.3% 0.29% 64 min
August 316 79.6% 0.32% 51 min
September 284 90.1% 0% 117 min
October 295 85.2% 1.02% 85 min
November 256 87% 0.39% 74 min
December 269 79.2% 1.49% 68 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.