Monday, October 12 · typical odds for a Monday (too early for a weather forecast) · issued Tue 12:00 AM ET · 3 nonstops

Mon, Oct 12: DL 3680 at 08:58 is the safest bet, 20% chance of being 15+ min late; the others run 27–33%.

Safest bet that day DL 3680 SEA 08:58 → TUS 12:16 · 20% chance 15+ min late · usually 94% on time Riskiest AS 648 SEA 11:35 → TUS 14:36 · 33% chance 15+ min late · usually 80% on time

Every nonstop on Mon, Oct 12

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.


DL 3680 Delta flown by SkyWest Flight history →	SEA 08:58	TUS 12:16	20%	5%	0.7%	94%worse than usual
AS 638 Alaska Flight history →	SEA 18:57	TUS 21:58	27%	6%	0.7%	82%
AS 648 Alaska Flight history →	SEA 11:35	TUS 14:36	33%	5%	1.4%	80%worse than usual

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 Mon, Oct 12 (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