Monday, October 5 · our forecast odds · issued Sun 12:00 PM ET · 25 nonstops

Tomorrow: WN 3753 at 05:50 is the safest bet, 13% chance of being 15+ min late; evening flights run 17–30%.

Safest bet that day WN 3753 SEA 05:50 → DEN 09:27 · 13% chance 15+ min late Riskiest AS 535 SEA 11:44 → DEN 15:38 · 36% chance 15+ min late · usually 78% on time

Against a calm day 24% average chance a nonstop arrives 15+ min late; 17% for the same flights on a calm-weather day

Every nonstop on Mon, Oct 5

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 3753 Southwest	SEA 05:50	DEN 09:27	13%	2%	0.5%	no record
WN 3615 Southwest Flight history →	SEA 05:15	DEN 08:50	13%	2%	0.5%	95%
UA 2601 United Flight history →	SEA 05:00	DEN 08:43	13%	3%	0.6%	96%
UA 1351 United Flight history →	SEA 12:50	DEN 16:42	17%	5%	0.6%	89%
UA 1218 United Flight history →	SEA 19:54	DEN 23:38	17%	6%	0.6%	84%
DL 2851 Delta Flight history →	SEA 19:59	DEN 23:44	18%	6%	0.6%	78%
UA 325 United Flight history →	SEA 15:40	DEN 19:29	22%	6%	0.6%	86%
UA 333 United Flight history →	SEA 14:33	DEN 18:22	22%	6%	0.6%	66%
AS 642 Alaska Flight history →	SEA 20:11	DEN 23:59	24%	5%	0.6%	81%
DL 1358 Delta Flight history →	SEA 08:10	DEN 12:02	24%	6%	0.6%	85%
AS 602 Alaska Flight history →	SEA 16:26	DEN 20:10	25%	6%	0.6%	76%
AS 310 Alaska Flight history →	SEA 19:00	DEN 22:45	25%	5%	0.6%	65%
AS 375 Alaska Flight history →	SEA 08:04	DEN 11:56	25%	7%	0.6%	88%worse than usual
UA 757 United Flight history →	SEA 11:02	DEN 14:51	25%	6%	0.6%	88%worse than usual
UA 1505 United Flight history →	SEA 08:56	DEN 12:45	25%	6%	0.6%	92%worse than usual
DL 2543 Delta Flight history →	SEA 13:50	DEN 17:43	25%	7%	0.6%	39%
WN 3397 Southwest Flight history →	SEA 07:50	DEN 11:25	26%	6%	0.5%	93%worse than usual
AS 682 Alaska Flight history →	SEA 07:05	DEN 10:49	27%	6%	0.6%	86%worse than usual
F9 1176 Frontier Flight history →	SEA 19:06	DEN 22:58	27%	9%	0.8%	78%
F9 3406 Frontier Flight history →	SEA 12:35	DEN 16:40	30%	8%	0.8%	78%
WN 4845 Southwest Flight history →	SEA 19:30	DEN 23:10	30%	9%	0.4%	40%
WN 3617 Southwest Flight history →	SEA 14:35	DEN 18:20	31%	6%	0.5%	14%
WN 3616 Southwest Flight history →	SEA 12:20	DEN 16:10	33%	6%	0.5%	44%
AS 242 Alaska Flight history →	SEA 13:33	DEN 17:20	35%	7%	0.6%	70%
AS 535 Alaska Flight history →	SEA 11:44	DEN 15:38	36%	6%	0.6%	78%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 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