Best time to fly Las Vegas to Portland

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

Best month

February

86% on time · 465 flights

Worst month

July

68.6% on time · 622 flights

Month Flights On time Cancelled When late, by
January 502 82.6% 0.4% 52 min
February 465 86% 1.51% 52 min
March 583 81.8% 0.86% 58 min
April 569 81.5% 0% 56 min
May 544 80.3% 0.37% 46 min
June 545 75.9% 1.1% 56 min
July 622 68.6% 2.09% 62 min
August 602 75.8% 0.5% 57 min
September 570 81.2% 0% 63 min
October 584 80.2% 0.68% 56 min
November 497 85.1% 0.4% 51 min
December 526 77.2% 0% 49 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.