Thursday, October 8 · typical odds for a Thursday (too early for a weather forecast) · issued Sun 12:00 PM ET · 9 nonstops

Thu, Oct 8: WN 3919 at 05:33 is the safest bet, 2% chance of being 15+ min late; the others run 3–22%.

Safest bet that day WN 3919 SMF 05:33 → LAS 07:05 · 2% chance 15+ min late Riskiest WN 374 SMF 14:01 → LAS 15:34 · 22% 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 3919 Southwest	SMF 05:33	LAS 07:05	2%	1%	0.7%	no record
WN 4360 Southwest	SMF 06:53	LAS 08:25	3%	1%	0.8%	no record
WN 4466 Southwest	SMF 08:06	LAS 09:38	5%	1%	0.8%	no record
WN 1940 Southwest Flight history →	SMF 10:36	LAS 12:08	13%	3%	0.7%	73%
WN 3928 Southwest	SMF 13:06	LAS 14:38	19%	4%	1.0%	no record
F9 4144 Frontier Flight history →	SMF 08:26	LAS 10:08	19%	6%	1.1%	74%
WN 2634 Southwest	SMF 16:56	LAS 18:28	20%	7%	0.6%	no record
WN 775 Southwest	SMF 15:21	LAS 16:54	21%	7%	0.8%	no record
WN 374 Southwest	SMF 14:01	LAS 15:34	22%	6%	0.9%	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