Today: AS 605 at 05:58 is the safest bet, 11% chance of being 15+ min late; evening flights run 17–50%.

Safest bet today AS 605 PHX 05:58 → SEA 08:54 · 11% chance 15+ min late · usually 93% on time Riskiest WN 3585 PHX 18:35 → SEA 21:30 · 50% chance 15+ min late · usually 36% on time

Against a calm day 24% 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.


AS 605 Alaska Flight history →	PHX 05:58	SEA 08:54	11%	2%	0.4%	93%
DL 1570 Delta Flight history →	PHX 06:59	SEA 10:05	13%	2%	0.1%	95%
AS 799 Alaska Flight history →	PHX 06:02	SEA 09:08	14%	3%	0.4%	83%
AA 3793 American flown by Envoy Flight history →	PHX 07:20	SEA 10:36	15%	3%	0.2%	86%
AA 3440 American flown by Envoy Flight history →	PHX 11:32	SEA 14:46	16%	4%	0.2%	86%
AA 4035 American flown by Envoy Flight history →	PHX 14:35	SEA 17:44	16%	4%	0.2%	83%
MQ 3831 Envoy	PHX 17:48	SEA 21:02	17%	5%	0.6%	no record
AA 3934 American flown by Envoy Flight history →	PHX 14:27	SEA 17:28	17%	4%	0.2%	89%
AA 4307 American flown by Envoy Flight history →	PHX 17:55	SEA 21:05	18%	5%	0.6%	84%
DL 2419 Delta Flight history →	PHX 12:15	SEA 15:25	18%	4%	0.1%	94%worse than usual
DL 2442 Delta Flight history →	PHX 17:40	SEA 20:46	19%	5%	0.7%	82%
DL 2374 Delta Flight history →	PHX 09:19	SEA 12:30	20%	3%	0.1%	91%worse than usual
MQ 3670 Envoy	PHX 07:48	SEA 10:50	20%	3%	0.2%	no record
AS 603 Alaska Flight history →	PHX 09:03	SEA 11:54	23%	3%	0.2%	89%worse than usual
AS 609 Alaska Flight history →	PHX 12:46	SEA 15:36	24%	4%	0.2%	83%
AS 645 Alaska Flight history →	PHX 07:20	SEA 10:29	25%	3%	0.3%	85%
WN 814 Southwest Flight history →	PHX 10:45	SEA 13:50	26%	3%	0.1%	81%
AA 2783 American	PHX 10:33	SEA 13:52	26%	6%	0.2%	no record
AS 425 Alaska Flight history →	PHX 14:37	SEA 17:43	26%	4%	0.2%	76%
WN 3330 Southwest Flight history →	PHX 08:35	SEA 11:40	26%	3%	0.1%	72%
AS 611 Alaska Flight history →	PHX 14:39	SEA 17:35	26%	4%	0.2%	81%
AS 637 Alaska Flight history →	PHX 11:32	SEA 14:22	28%	4%	0.3%	86%worse than usual
WN 800 Southwest	PHX 07:50	SEA 10:42	30%	3%	0.1%	no record
AS 477 Alaska	PHX 19:03	SEA 22:00	30%	6%	0.6%	no record
DL 2449 Delta Flight history →	PHX 15:54	SEA 19:02	31%	5%	0.1%	83%worse than usual
AS 1422 Alaska	PHX 16:13	SEA 19:09	33%	6%	0.2%	no record
AS 289 Alaska Flight history →	PHX 16:00	SEA 19:06	33%	6%	0.2%	67%
WN 3046 Southwest	PHX 22:30	SEA 01:22	39%	9%	0.5%	no record
WN 2970 Southwest	PHX 13:30	SEA 16:21	43%	4%	0.1%	no record
WN 3585 Southwest Flight history →	PHX 18:35	SEA 21:30	50%	13%	0.5%	36%

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