Best time to fly Burbank to Seattle

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

Best month

September

92% on time · 127 flights

Worst month

July

73% on time · 149 flights

Month Flights On time Cancelled When late, by
January 110 88.9% 1.82% 109 min
February 94 91.3% 2.13% 155 min
March 123 85.2% 3.25% 61 min
April 136 88.9% 0.74% 35 min
May 142 84.6% 4.23% 65 min
June 164 83.6% 3.05% 55 min
July 149 73% 5.37% 37 min
August 140 75.7% 2.86% 51 min
September 127 92% 1.57% 37 min
October 131 80% 3.82% 54 min
November 127 76.6% 1.57% 79 min
December 143 81.4% 1.4% 52 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.