Today looks rough: weather pushes the average chance of arriving 15+ min late to 34%, against 18% on a calm day. Safest: WN 3284 at 08:00, 17%.

Safest bet today WN 3284 PDX 08:00 → SAN 10:37 · 17% chance 15+ min late Riskiest AS 1320 PDX 14:53 → SAN 17:29 · 45% chance 15+ min late

Weather 34% average chance a nonstop arrives 15+ min late; 18% 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.


WN 3284 Southwest	PDX 08:00	SAN 10:37	17%	3%	0.2%	no record
AS 577 Alaska Flight history →	PDX 07:32	SAN 10:05	24%	4%	0.8%	80%
AS 369 Alaska Flight history →	PDX 17:40	SAN 20:18	27%	5%	0.6%	57%
AS 667 Alaska Flight history →	PDX 17:38	SAN 20:12	28%	5%	0.6%	78%
AS 721 Alaska Flight history →	PDX 09:03	SAN 11:40	31%	7%	1.0%	80%worse than usual
WN 2809 Southwest Flight history →	PDX 13:05	SAN 15:30	38%	7%	0.2%	50%
AS 1394 Alaska Flight history →	PDX 10:46	SAN 13:27	38%	8%	0.7%	84%worse than usual
AS 1371 Alaska	PDX 13:49	SAN 16:25	42%	9%	0.9%	no record
AS 1312 Alaska Flight history →	PDX 14:55	SAN 17:29	42%	7%	0.8%	76%worse than usual
WN 3155 Southwest	PDX 16:10	SAN 18:44	45%	10%	0.3%	no record
AS 1320 Alaska	PDX 14:53	SAN 17:29	45%	8%	0.8%	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 Mon, Oct 5 (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