Today: WN 4457 at 05:00 is the safest bet, 3% chance of being 15+ min late; the others run 11–16%.

Safest bet today WN 4457 GEG 05:00 → LAS 07:24 · 3% chance 15+ min late Riskiest WN 1951 GEG 17:10 → LAS 19:35 · 16% chance 15+ min late · usually 81% on time

Against a calm day 11% average chance a nonstop arrives 15+ min late; 10% 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.


WN 4457 Southwest	GEG 05:00	LAS 07:24	3%	1%	0.2%	no record
WN 1782 Southwest Flight history →	GEG 09:50	LAS 12:10	11%	2%	0.2%	85%
WN 2474 Southwest	GEG 14:30	LAS 16:56	14%	3%	0.4%	no record
WN 1951 Southwest Flight history →	GEG 17:10	LAS 19:35	16%	3%	0.4%	81%

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 Mon, Oct 5 (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