Friday, October 9 · typical odds for a Friday (too early for a weather forecast) · issued Sat 8:00 PM ET · 19 nonstops

Fri, Oct 9: WN 4231 at 05:00 is the safest bet, 3% chance of being 15+ min late; evening flights run 26–43%.

Safest bet that day WN 4231 SFO 05:00 → LAS 06:35 · 3% chance 15+ min late · usually 90% on time Riskiest F9 4156 SFO 21:00 → LAS 22:48 · 43% chance 15+ min late · usually 55% on time

Every nonstop on Fri, Oct 9

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 4231 Southwest Flight history →	SFO 05:00	LAS 06:35	3%	1%	0.6%	90%
UA 582 United Flight history →	SFO 06:00	LAS 07:46	4%	1%	0.6%	98%
AS 718 Alaska Flight history →	SFO 07:25	LAS 09:05	10%	3%	0.6%	91%
UA 2382 United Flight history →	SFO 08:42	LAS 10:28	13%	4%	0.6%	75%
WN 4249 Southwest Flight history →	SFO 09:45	LAS 11:20	18%	7%	0.6%	22%
UA 1995 United Flight history →	SFO 19:37	LAS 21:27	26%	10%	0.6%	81%
UA 611 United Flight history →	SFO 10:42	LAS 12:28	28%	9%	0.6%	80%
UA 751 United Flight history →	SFO 17:37	LAS 19:27	29%	12%	0.6%	72%
UA 2855 United Flight history →	SFO 14:21	LAS 16:11	30%	11%	0.6%	62%
UA 2839 United Flight history →	SFO 22:59	LAS 00:46	30%	10%	0.6%	59%
UA 2449 United Flight history →	SFO 12:00	LAS 13:50	31%	10%	0.6%	66%
UA 406 United Flight history →	SFO 21:15	LAS 23:10	31%	11%	0.6%	77%
AS 776 Alaska Flight history →	SFO 15:52	LAS 17:33	37%	13%	0.7%	63%
AS 468 Alaska Flight history →	SFO 21:59	LAS 23:42	40%	12%	0.7%	40%
WN 3644 Southwest Flight history →	SFO 13:20	LAS 15:00	40%	16%	0.7%	17%
F9 4158 Frontier Flight history →	SFO 11:20	LAS 13:10	41%	17%	1.4%	67%
WN 1288 Southwest Flight history →	SFO 15:45	LAS 17:25	41%	17%	0.7%	4%
F9 1850 Frontier Flight history →	SFO 15:43	LAS 17:30	42%	20%	1.3%	69%worse than usual
F9 4156 Frontier Flight history →	SFO 21:00	LAS 22:48	43%	21%	1.7%	55%

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 Fri, Oct 9 (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