Best time to fly Washington to New York

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

Best month

September

83.9% on time · 741 flights

Worst month

December

63.5% on time · 667 flights

Month Flights On time Cancelled When late, by
January 774 79.4% 8.79% 67 min
February 746 65.1% 7.51% 78 min
March 825 64.9% 6.18% 72 min
April 806 70.8% 0.87% 62 min
May 813 65.9% 3.69% 73 min
June 809 69.1% 6.8% 93 min
July 789 71.2% 10.14% 74 min
August 771 77.1% 6.1% 87 min
September 741 83.9% 0.94% 69 min
October 769 77.4% 2.08% 72 min
November 760 68.4% 2.5% 72 min
December 667 63.5% 1.8% 69 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.