Today looks rough: weather pushes the average chance of arriving 15+ min late to 33%, against 20% on a calm day. Safest: UA 6030 at 15:15, 26%.

Safest bet today UA 6030 DEN 15:15 → BZN 17:10 · 26% chance 15+ min late · usually 74% on time Riskiest WN 4675 DEN 21:00 → BZN 22:49 · 39% chance 15+ min late

Weather 33% 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.


UA 6030 United flown by SkyWest Flight history →	DEN 15:15	BZN 17:10	26%	6%	0.5%	74%
UA 513 United Flight history →	DEN 13:44	BZN 15:33	26%	6%	0.2%	85%worse than usual
WN 4530 Southwest	DEN 15:55	BZN 17:44	35%	6%	0.2%	no record
UA 1347 United Flight history →	DEN 19:25	BZN 21:14	35%	8%	0.2%	80%worse than usual
WN 1505 Southwest Flight history →	DEN 21:10	BZN 23:00	39%	11%	0.2%	46%
WN 4675 Southwest	DEN 21:00	BZN 22:49	39%	10%	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