Saturday, October 10 · typical odds for a Saturday (too early for a weather forecast) · issued Sun 12:00 AM ET · 5 nonstops

Sat, Oct 10 looks like a normal day here: all 5 nonstops are 14–22% likely to arrive 15+ min late.

Safest bet that day UA 800 SEA 23:05 → IAD 06:45 · 14% chance 15+ min late Riskiest DL 541 SEA 11:58 → IAD 20:04 · 22% chance 15+ min late · usually 77% on time

Every nonstop on Sat, Oct 10

12-month record →

Ranked by the chance of arriving 15+ minutes late (typical odds: the weather this date has had in past years), 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.


UA 800 United	SEA 23:05	IAD 06:45	14%	3%	0.6%	no record
UA 1523 United	SEA 08:29	IAD 16:37	16%	4%	0.6%	no record
AS 366 Alaska	SEA 16:12	IAD 23:46	18%	5%	0.6%	no record
AS 737 Alaska Flight history →	SEA 09:13	IAD 17:11	21%	5%	0.6%	84%
DL 541 Delta Flight history →	SEA 11:58	IAD 20:04	22%	6%	0.6%	77%

How these are worked out. Each flight’s odds are our forecast for that day (typical odds until the weather forecast covers it); 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 Sat, Oct 10 (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