Best time to fly Boston to New Orleans

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

Best month

September

91.5% on time · 60 flights

Worst month

December

59.7% on time · 74 flights

Month Flights On time Cancelled When late, by
January 64 61.7% 6.25% 78 min
February 70 70.8% 7.14% 150 min
March 79 78.2% 1.27% 68 min
April 78 84.6% 0% 70 min
May 77 80.5% 0% 45 min
June 60 78.3% 0% 54 min
July 62 69.4% 0% 95 min
August 54 72.2% 0% 87 min
September 60 91.5% 1.67% 97 min
October 97 83.5% 0% 59 min
November 80 82.3% 0% 41 min
December 74 59.7% 2.7% 63 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.