Today looks rough: weather pushes the average chance of arriving 15+ min late to 42%, against 26% on a calm day. Safest: DL 481 at 14:38, 36%.

Safest bet today DL 481 ATL 14:38 → SEA 16:49 · 36% chance 15+ min late · usually 80% on time Riskiest DL 714 ATL 17:50 → SEA 20:11 · 48% chance 15+ min late · usually 67% on time

Weather 42% average chance a nonstop arrives 15+ min late; 26% 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. 6 flights that already left today are not shown.


DL 481 Delta Flight history →	ATL 14:38	SEA 16:49	36%	10%	0.2%	80%worse than usual
AS 218 Alaska Flight history →	ATL 16:18	SEA 18:46	39%	14%	0.8%	62%
DL 472 Delta Flight history →	ATL 16:45	SEA 19:05	45%	13%	0.2%	70%worse than usual
DL 903 Delta Flight history →	ATL 21:35	SEA 23:59	45%	10%	0.2%	79%worse than usual
DL 714 Delta Flight history →	ATL 17:50	SEA 20:11	48%	13%	0.3%	67%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