Best time to fly St. Louis to Minneapolis

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

Best month

October

87.1% on time · 315 flights

Worst month

July

68.6% on time · 319 flights

Month Flights On time Cancelled When late, by
January 296 81% 2.03% 99 min
February 294 82.9% 0.68% 76 min
March 356 82.5% 1.97% 86 min
April 334 82.6% 0.3% 87 min
May 317 86.1% 0.32% 75 min
June 309 73.2% 0.97% 73 min
July 319 68.6% 2.82% 81 min
August 332 82.5% 0.3% 72 min
September 336 85.4% 0% 66 min
October 315 87.1% 1.27% 65 min
November 293 85.7% 0% 85 min
December 316 73.4% 1.27% 81 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.