Tuesday, October 6 · our forecast odds · issued Mon 4:00 PM ET · 5 nonstops

Tomorrow: UA 2637 at 09:58 is the safest bet, 9% chance of being 15+ min late; evening flights run 17–24%.

Safest bet that day UA 2637 DEN 09:58 → GRR 14:35 · 9% chance 15+ min late · usually 88% on time Riskiest WN 1502 DEN 16:48 → GRR 21:11 · 24% chance 15+ min late

Against a calm day 15% average chance a nonstop arrives 15+ min late; 14% for the same flights on a calm-weather day

Every nonstop on Tue, Oct 6

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.


UA 2637 United Flight history →	DEN 09:58	GRR 14:35	9%	2%	0.4%	88%
F9 1248 Frontier Flight history →	DEN 10:50	GRR 15:33	9%	3%	0.6%	89%
WN 1500 Southwest	DEN 11:55	GRR 16:28	15%	3%	0.5%	no record
UA 2121 United Flight history →	DEN 17:55	GRR 22:35	17%	4%	0.4%	71%
WN 1502 Southwest	DEN 16:48	GRR 21:11	24%	3%	0.5%	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 Tue, Oct 6 (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