Today: WN 3062 at 11:55 is the safest bet, 17% chance of being 15+ min late; the others run 30–35%.

Safest bet today WN 3062 ONT 11:55 → DEN 15:10 · 17% chance 15+ min late Riskiest WN 8500 ONT 14:44 → DEN 18:07 · 35% chance 15+ min late

Against a calm day 29% average chance a nonstop arrives 15+ min late; 20% for the same flights on a calm-weather day

Every nonstop today

12-month record →

Ranked by the chance of arriving 15+ minutes late, 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. 7 flights that already left today are not shown.


WN 3062 Southwest	ONT 11:55	DEN 15:10	17%	4%	0.2%	no record
WN 670 Southwest	ONT 15:10	DEN 18:20	30%	7%	0.2%	no record
UA 1263 United Flight history →	ONT 13:18	DEN 16:38	30%	9%	0.4%	84%worse than usual
WN 1758 Southwest	ONT 17:41	DEN 20:58	31%	9%	0.2%	no record
WN 3288 Southwest	ONT 14:51	DEN 18:08	33%	7%	0.2%	no record
WN 8500 Southwest	ONT 14:44	DEN 18:07	35%	7%	0.2%	no record

How these are worked out. Each flight’s odds are our forecast for that day; 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 4 (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