Sunday, October 11 · typical odds for a Sunday (too early for a weather forecast) · issued Mon 12:00 AM ET · 9 nonstops

Sun, Oct 11: WN 4115 at 05:20 is the safest bet, 4% chance of being 15+ min late; the others run 6–39%.

Safest bet that day WN 4115 ONT 05:20 → DEN 08:39 · 4% chance 15+ min late Riskiest WN 3288 ONT 14:50 → DEN 18:08 · 39% chance 15+ min late

Every nonstop on Sun, Oct 11

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 05:20	DEN 08:39	4%	1%	0.5%	no record
UA 2446 United Flight history →	ONT 05:00	DEN 08:20	6%	3%	0.6%	94%
WN 2102 Southwest	ONT 09:45	DEN 13:04	10%	3%	0.5%	no record
F9 1500 Frontier Flight history →	ONT 06:00	DEN 09:24	13%	4%	0.7%	90%
F9 2908 Frontier Flight history →	ONT 10:49	DEN 14:10	21%	6%	0.7%	77%
UA 1263 United Flight history →	ONT 13:18	DEN 16:38	31%	11%	0.6%	84%worse than usual
WN 1758 Southwest	ONT 17:40	DEN 20:58	33%	11%	0.6%	no record
WN 8500 Southwest	ONT 14:43	DEN 18:07	38%	11%	0.6%	no record
WN 3288 Southwest	ONT 14:50	DEN 18:08	39%	10%	0.6%	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 Sun, Oct 11 (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