Best time to fly Portland to Anchorage

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

Best month

April

90.3% on time · 93 flights

Worst month

December

60.4% on time · 92 flights

Month Flights On time Cancelled When late, by
January 68 79.4% 0% 60 min
February 81 81.5% 0% 27 min
March 112 87.5% 0% 68 min
April 93 90.3% 0% 69 min
May 112 88.3% 0% 45 min
June 120 86.7% 0% 47 min
July 93 68.8% 0% 48 min
August 94 78.7% 0% 53 min
September 90 87.8% 0% 30 min
October 117 73.5% 0% 49 min
November 107 88.8% 0% 29 min
December 92 60.4% 0% 48 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.