Today looks rough: weather pushes the average chance of arriving 15+ min late to 29%, against 19% on a calm day. Safest: AS 1 at 08:00, 26%.

Safest bet today AS 1 DCA 08:00 → SEA 10:58 · 26% chance 15+ min late · usually 82% on time Riskiest AS 3 DCA 17:00 → SEA 19:59 · 31% chance 15+ min late · usually 75% on time

Weather 29% average chance a nonstop arrives 15+ min late; 19% 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.


AS 1 Alaska Flight history →	DCA 08:00	SEA 10:58	26%	5%	0.6%	82%
DL 786 Delta Flight history →	DCA 16:35	SEA 19:41	31%	6%	0.2%	66%
AS 3 Alaska Flight history →	DCA 17:00	SEA 19:59	31%	7%	0.4%	75%

Alternatives with one stop that day

All connections →


Delta Details →	DCA 07:45 → MSP 09:25DL 1493	1h 45m Minneapolis	MSP 11:10 → SEA 13:00DL 889	8h 15m	96%	82%
Southwest Details →	DCA 08:00 → STL 09:10WN 4853	2h 30m St Louis	STL 11:40 → SEA 13:55WN 3981	8h 55m	100%	79%
Alaska Details →	DCA 17:16 → PDX 20:04AS 9	1h 26m Portland	PDX 21:30 → SEA 22:27AS 2421 · flown by Horizon	8h 11m	88%	79%

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