Today: AS 518 at 19:59 is the safest bet, 14% chance of being 15+ min late; the others run 17–28%.

Safest bet today AS 518 PDX 19:59 → SNA 22:30 · 14% chance 15+ min late · usually 96% on time Riskiest AS 264 PDX 14:48 → SNA 17:19 · 28% chance 15+ min late · usually 92% on time

Against a calm day 22% average chance a nonstop arrives 15+ min late; 12% for the same flights on a calm-weather day

Every nonstop today

12-month record →

Ranked by the chance of arriving 15+ minutes late, with each flight’s on-time record over Aug 2025 – Jul 2026 beside it. Times are local. Pick a flight for its forecast. Click a column to sort. 2 flights that already left today are not shown.


AS 518 Alaska Flight history →	PDX 19:59	SNA 22:30	14%	6%	0.6%	96%worse than usual
AS 1472 Alaska	PDX 19:41	SNA 22:15	17%	7%	0.6%	no record
AS 574 Alaska	PDX 17:32	SNA 20:05	28%	10%	0.6%	no record
AS 264 Alaska Flight history →	PDX 14:48	SNA 17:19	28%	7%	0.6%	92%worse than usual

How these are worked out. Each flight’s odds are our forecast for that day; flights of airlines we don’t forecast yet use their 12-month record and are marked. Makes the connection: the first flight’s 12-month lateness curve, scaled so its chance of arriving 15+ min late matches the day’s forecast, at the layover minus the 45-minute minimum (90 on separate tickets). Arrives on time: first flight not cancelled × connection made × second flight not cancelled × second flight within 15 minutes, each from the day’s forecast.

About this data: forecast odds from our model for Sun, Oct 4 (newest published update); 12-month records from US DOT on-time data, Aug 2025 – Jul 2026, all US airlines; regional flights count under the airline that sells them. JSON