Friday, October 9 · typical odds for a Friday (too early for a weather forecast) · issued Sun 4:00 PM ET · 7 nonstops

Fri, Oct 9 looks like a normal day here: all 3 nonstops are 22–28% likely to arrive 15+ min late.

Safest bet that day DL 3992 SEA 10:35 → PSC 11:43 · 22% chance 15+ min late · usually 86% on time Riskiest DL 4017 SEA 22:45 → PSC 23:53 · 28% chance 15+ min late · usually 83% on time

Every nonstop on Fri, Oct 9

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. Dimmed: airlines we don’t forecast yet, shown with their 12-month record if they usually fly that weekday.


DL 3992 Delta flown by SkyWest Flight history →	SEA 10:35	PSC 11:43	22%	6%	0.6%	86%
DL 3891 Delta flown by SkyWest Flight history →	SEA 13:40	PSC 14:54	25%	7%	0.6%	83%
DL 4017 Delta flown by SkyWest Flight history →	SEA 22:45	PSC 23:53	28%	7%	0.7%	83%worse than usual
AS 2195 Alaska flown by Horizon no forecast: 12-month record	SEA 08:52	PSC 09:53	10%	0%	0.0%	90%
AS 2403 Alaska flown by Horizon no forecast: 12-month record	SEA 22:44	PSC 23:43	13%	3%	0.0%	87%
AS 2367 Alaska flown by Horizon no forecast: 12-month record	SEA 16:28	PSC 17:27	18%	2%	0.7%	82%
AS 2306 Alaska flown by Horizon no forecast: 12-month record	SEA 11:20	PSC 12:19	42%	8%	0.0%	58%

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 Fri, Oct 9 (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