Today looks rough: weather pushes the average chance of arriving 15+ min late to 48%, against 27% on a calm day. Safest: AS 71 at 21:23, 46%.

Safest bet today AS 71 SEA 21:23 → JNU 22:55 · 46% chance 15+ min late · usually 72% on time Riskiest AS 1559 SEA 19:50 → JNU 21:22 · 49% chance 15+ min late · usually 73% on time

Weather 48% average chance a nonstop arrives 15+ min late; 27% 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. 5 flights that already left today are not shown.


AS 71 Alaska Flight history →	SEA 21:23	JNU 22:55	46%	8%	0.8%	72%worse than usual
AS 486 Alaska	SEA 20:10	JNU 21:47	48%	10%	0.8%	no record
AS 1559 Alaska Flight history →	SEA 19:50	JNU 21:22	49%	9%	0.8%	73%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 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