Thursday, October 8 · typical odds for a Thursday (too early for a weather forecast) · issued Sun 12:00 PM ET · 10 nonstops

Thu, Oct 8: WN 3909 at 05:36 is the safest bet, 2% chance of being 15+ min late; the others run 4–19%.

Safest bet that day WN 3909 SMF 05:36 → DEN 09:08 · 2% chance 15+ min late Riskiest WN 932 SMF 14:43 → DEN 18:15 · 19% chance 15+ min late

Every nonstop on Thu, Oct 8

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 3909 Southwest	SMF 05:36	DEN 09:08	2%	1%	0.5%	no record
UA 1889 United Flight history →	SMF 05:00	DEN 08:22	4%	1%	0.6%	97%
UA 2285 United Flight history →	SMF 08:50	DEN 12:16	6%	2%	0.6%	98%
WN 3837 Southwest	SMF 10:46	DEN 14:18	7%	2%	0.5%	no record
UA 1055 United	SMF 10:53	DEN 14:38	10%	3%	0.6%	no record
UA 1961 United Flight history →	SMF 13:00	DEN 16:26	13%	3%	0.6%	85%
WN 3911 Southwest	SMF 12:11	DEN 15:43	13%	2%	0.5%	no record
UA 566 United Flight history →	SMF 16:19	DEN 19:45	15%	4%	0.6%	87%
F9 3666 Frontier Flight history →	SMF 11:27	DEN 15:06	16%	5%	0.6%	82%
WN 932 Southwest	SMF 14:43	DEN 18:15	19%	3%	0.5%	no record

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 Thu, Oct 8 (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