Today: WN 3331 at 05:52 is the safest bet, 3% chance of being 15+ min late; evening flights run 13–19%.

Safest bet today WN 3331 PDX 05:52 → SMF 07:34 · 3% chance 15+ min late Riskiest WN 3212 PDX 12:15 → SMF 13:45 · 24% chance 15+ min late · usually 81% on time

Against a calm day 15% average chance a nonstop arrives 15+ min late; 11% 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. Dimmed: airlines we don’t forecast yet, shown with their 12-month record if they usually fly that weekday.


WN 3331 Southwest	PDX 05:52	SMF 07:34	3%	1%	0.1%	no record
WN 3211 Southwest Flight history →	PDX 05:30	SMF 07:00	3%	1%	0.2%	98%
AS 433 Alaska	PDX 14:48	SMF 16:27	11%	3%	0.6%	no record
OO 3374 SkyWest	PDX 08:02	SMF 09:48	12%	4%	0.2%	no record
AS 793 Alaska	PDX 17:48	SMF 19:28	13%	3%	0.6%	no record
AS 1622 Alaska Flight history →	PDX 17:59	SMF 19:37	14%	3%	0.6%	79%
WN 3214 Southwest Flight history →	PDX 22:10	SMF 23:45	15%	5%	0.5%	23%
WN 4355 Southwest	PDX 10:15	SMF 11:57	16%	3%	0.1%	no record
WN 1717 Southwest	PDX 14:55	SMF 16:37	16%	3%	0.4%	no record
WN 3213 Southwest Flight history →	PDX 20:15	SMF 21:50	18%	5%	0.5%	58%
AS 653 Alaska	PDX 10:30	SMF 12:10	18%	3%	0.3%	no record
WN 3612 Southwest	PDX 20:20	SMF 22:01	19%	5%	0.5%	no record
WN 300 Southwest Flight history →	PDX 10:00	SMF 11:25	20%	3%	0.1%	69%
WN 3212 Southwest Flight history →	PDX 12:15	SMF 13:45	24%	4%	0.1%	81%
AS 2399 Alaska flown by Horizon no forecast: 12-month record	PDX 11:00	SMF 12:33	9%	1%	0.6%	91%
AS 2405 Alaska flown by Horizon no forecast: 12-month record	PDX 14:32	SMF 16:06	12%	0%	1.9%	88%

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