Best time to fly Fort Lauderdale to Islip

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

Best month

October

91.7% on time · 25 flights

Worst month

March

64.9% on time · 81 flights

Month Flights On time Cancelled When late, by
January 60 68.4% 5% 70 min
February 66 78.1% 3.03% 80 min
March 81 64.9% 3.7% 58 min
April 77 80.3% 0% 73 min
May 83 79.3% 0% 64 min
June 61 88.5% 0% 69 min
July 62 70.5% 1.61% 49 min
August 67 71.9% 4.48% 71 min
September 22 90.9% 0% 64 min
October 25 91.7% 0% 20 min
November 51 76.5% 0% 61 min
December 78 72% 3.85% 75 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.