Best time to fly Des Moines to New York

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

Best month

September

94.1% on time · 102 flights

Worst month

December

66.7% on time · 90 flights

Month Flights On time Cancelled When late, by
January 49 79.2% 2.04% 67 min
February 48 69.6% 4.17% 86 min
March 53 69.4% 7.55% 53 min
April 52 92.3% 0% 25 min
May 49 81.6% 0% 53 min
June 52 84.3% 0% 150 min
July 102 82.4% 9.8% 70 min
August 105 80.2% 8.57% 104 min
September 102 94.1% 0% 25 min
October 105 89.5% 0% 64 min
November 98 91.8% 0% 55 min
December 90 66.7% 0% 90 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.