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

Thu, Oct 8: WN 4115 at 05:42 is the safest bet, 4% chance of being 15+ min late; the others run 6–21%.

Safest bet that day WN 4115 ONT 05:42 → DEN 09:04 · 4% chance 15+ min late Riskiest WN 3264 ONT 14:51 → DEN 18:13 · 21% 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 4115 Southwest	ONT 05:42	DEN 09:04	4%	1%	0.5%	no record
UA 2446 United Flight history →	ONT 05:00	DEN 08:20	6%	2%	0.6%	94%
WN 3263 Southwest	ONT 08:08	DEN 11:30	8%	2%	0.5%	no record
F9 1500 Frontier Flight history →	ONT 06:00	DEN 09:24	14%	3%	0.7%	90%
UA 1263 United Flight history →	ONT 13:18	DEN 16:38	16%	6%	0.6%	84%
WN 3291 Southwest	ONT 12:43	DEN 16:05	17%	4%	0.5%	no record
F9 2908 Frontier Flight history →	ONT 10:49	DEN 14:10	18%	5%	0.7%	77%
WN 3264 Southwest	ONT 14:51	DEN 18:13	21%	6%	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