Today looks rough: weather pushes the average chance of arriving 15+ min late to 61%, against 25% on a calm day. Safest: DL 448 at 23:15, 56%.

Safest bet today DL 448 SEA 23:15 → MCO 07:40 · 56% chance 15+ min late · usually 85% on time Riskiest AS 390 SEA 21:29 → MCO 05:52 · 63% chance 15+ min late

Weather 61% average chance a nonstop arrives 15+ min late; 25% 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. 2 flights that already left today are not shown.


DL 448 Delta Flight history →	SEA 23:15	MCO 07:40	56%	14%	0.8%	85%worse than usual
AS 394 Alaska Flight history →	SEA 21:33	MCO 06:16	60%	13%	0.7%	87%worse than usual
AS 420 Alaska Flight history →	SEA 15:27	MCO 23:50	63%	20%	0.7%	82%worse than usual
AS 390 Alaska	SEA 21:29	MCO 05:52	63%	14%	0.7%	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