Best time to fly Los Angeles to Washington

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

Best month

October

96% on time · 202 flights

Worst month

July

71% on time · 221 flights

Month Flights On time Cancelled When late, by
January 174 82% 4.02% 76 min
February 158 88% 0% 46 min
March 184 75.8% 0% 48 min
April 225 94.2% 0% 104 min
May 252 90.8% 0% 50 min
June 253 90.4% 0.79% 57 min
July 221 71% 1.36% 72 min
August 198 86.7% 0.51% 56 min
September 174 91.9% 0.57% 53 min
October 202 96% 0.99% 42 min
November 198 83.8% 0% 47 min
December 215 86.4% 0.47% 38 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.