Monday, October 12 · typical odds for a Monday (too early for a weather forecast) · issued Tue 12:00 AM ET · 18 nonstops

Mon, Oct 12: WN 3641 at 06:15 is the safest bet, 9% chance of being 15+ min late; evening flights run 27–44%.

Safest bet that day WN 3641 SAN 06:15 → DEN 09:35 · 9% chance 15+ min late Riskiest F9 4990 SAN 16:50 → DEN 20:20 · 44% chance 15+ min late · usually 81% on time

Every nonstop on Mon, Oct 12

12-month record →

Ranked by the chance of arriving 15+ minutes late (typical odds: the weather this date has had in past years), 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 3641 Southwest	SAN 06:15	DEN 09:35	9%	2%	0.7%	no record
UA 2829 United	SAN 07:03	DEN 10:47	16%	5%	0.7%	no record
UA 2476 United Flight history →	SAN 08:45	DEN 12:17	19%	5%	0.7%	89%
WN 1934 Southwest	SAN 08:15	DEN 11:38	19%	4%	0.6%	no record
F9 2818 Frontier Flight history →	SAN 06:25	DEN 10:03	22%	5%	1.3%	86%
AS 1342 Alaska	SAN 07:59	DEN 11:16	23%	4%	0.8%	no record
UA 2793 United	SAN 11:03	DEN 14:47	24%	8%	0.7%	no record
WN 1840 Southwest	SAN 10:52	DEN 14:12	27%	4%	0.6%	no record
UA 519 United Flight history →	SAN 18:55	DEN 22:27	27%	10%	1.0%	88%worse than usual
OO 3121 SkyWest	SAN 20:19	DEN 23:47	28%	10%	1.8%	no record
UA 1565 United Flight history →	SAN 12:33	DEN 16:06	28%	8%	0.7%	87%worse than usual
WN 4492 Southwest	SAN 21:14	DEN 00:37	29%	8%	0.8%	no record
UA 682 United Flight history →	SAN 16:01	DEN 19:33	37%	12%	0.7%	77%worse than usual
WN 3286 Southwest	SAN 18:20	DEN 21:40	37%	11%	1.1%	no record
AS 635 Alaska	SAN 14:59	DEN 18:12	38%	8%	0.8%	no record
WN 1329 Southwest	SAN 16:07	DEN 19:27	40%	9%	0.7%	no record
WN 2019 Southwest	SAN 15:29	DEN 18:51	41%	9%	0.7%	no record
F9 4990 Frontier Flight history →	SAN 16:50	DEN 20:20	44%	15%	1.6%	81%worse than usual

How these are worked out. Each flight’s odds are our forecast for that day (typical odds until the weather forecast covers it); 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 12 (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