Today looks rough: weather pushes the average chance of arriving 15+ min late to 38%, against 21% on a calm day. Safest: OO 3341 at 21:05, 26%.

Safest bet today OO 3341 PDX 21:05 → SJC 23:09 · 26% chance 15+ min late Riskiest WN 3329 PDX 21:10 → SJC 23:10 · 48% chance 15+ min late

Weather 38% average chance a nonstop arrives 15+ min late; 21% 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. 10 flights that already left today are not shown.


OO 3341 SkyWest	PDX 21:05	SJC 23:09	26%	10%	0.4%	no record
AS 678 Alaska Flight history →	PDX 21:30	SJC 23:21	31%	11%	0.2%	81%worse than usual
WN 1670 Southwest Flight history →	PDX 21:00	SJC 22:50	48%	22%	0.2%	30%
WN 3329 Southwest	PDX 21:10	SJC 23:10	48%	25%	0.2%	no record

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