Best time to fly St. Louis to Tampa

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

Best month

January

85.2% on time · 196 flights

Worst month

July

66% on time · 200 flights

Month Flights On time Cancelled When late, by
January 196 85.2% 3.57% 49 min
February 176 82.3% 0.57% 45 min
March 236 80.9% 2.12% 66 min
April 210 81.9% 0% 49 min
May 217 82.3% 0.92% 68 min
June 198 76.5% 0% 53 min
July 200 66% 0.5% 43 min
August 189 77.3% 1.06% 53 min
September 179 82.2% 2.23% 37 min
October 191 84.1% 4.71% 64 min
November 187 82.8% 0.53% 66 min
December 204 80.2% 0% 53 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.