Best time to fly Marignane to London

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

Best month

April

86.5% on time · 89 flights

Worst month

July

29.3% on time · 62 flights

Month Flights On time Cancelled When late, by
January 46 76.1% 0% 0 min
February 50 82% 0% 0 min
March 67 82.1% 0% 0 min
April 89 86.5% 0% 0 min
May 98 69.4% 0% 0 min
June 99 47.9% 3.03% 0 min
July 62 29.3% 6.45% 0 min
August 62 52.5% 1.61% 0 min
September 51 51% 0% 0 min
October 54 75.9% 0% 0 min
November 25 80% 0% 0 min
December 45 84.4% 0% 0 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.