Today: UA 2258 at 14:26 is the safest bet, 30% chance of being 15+ min late; evening flights run 35–51%.

Safest bet today UA 2258 BZN 14:26 → DEN 16:20 · 30% chance 15+ min late · usually 82% on time Riskiest WN 3898 BZN 16:21 → DEN 18:03 · 51% chance 15+ min late

Against a calm day 40% average chance a nonstop arrives 15+ min late; 30% 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. 6 flights that already left today are not shown.


UA 2258 United Flight history →	BZN 14:26	DEN 16:20	30%	9%	0.2%	82%worse than usual
UA 5736 United flown by SkyWest Flight history →	BZN 17:51	DEN 19:58	35%	11%	0.4%	65%
UA 431 United Flight history →	BZN 16:32	DEN 18:39	39%	11%	0.2%	65%
WN 1132 Southwest Flight history →	BZN 14:15	DEN 16:00	39%	6%	0.1%	33%
UA 1322 United Flight history →	BZN 16:29	DEN 18:23	39%	11%	0.2%	58%
WN 1133 Southwest Flight history →	BZN 16:30	DEN 18:20	49%	8%	0.1%	43%
WN 3898 Southwest	BZN 16:21	DEN 18:03	51%	8%	0.1%	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