Today looks rough: weather pushes the average chance of arriving 15+ min late to 59%, against 37% on a calm day. Safest: AS 691 at 20:59, 50%.

Safest bet today AS 691 LAS 20:59 → SEA 23:31 · 50% chance 15+ min late Riskiest AS 552 LAS 19:50 → SEA 21:45 · 62% chance 15+ min late · usually 83% on time

Weather 59% average chance a nonstop arrives 15+ min late; 37% 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. 19 flights that already left today are not shown.


AS 691 Alaska	LAS 20:59	SEA 23:31	50%	12%	0.6%	no record
WN 269 Southwest	LAS 22:52	SEA 01:45	60%	15%	0.2%	no record
WN 4196 Southwest Flight history →	LAS 22:30	SEA 01:15	62%	17%	0.2%	50%worse than usual
AS 552 Alaska Flight history →	LAS 19:50	SEA 21:45	62%	20%	0.6%	83%worse than usual

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