Sunday, October 11 · typical odds for a Sunday (too early for a weather forecast) · issued Mon 12:00 AM ET · 13 nonstops

Sun, Oct 11: WN 3980 at 06:30 is the safest bet, 9% chance of being 15+ min late; evening flights run 29–50%.

Safest bet that day WN 3980 SMF 06:30 → SEA 08:28 · 9% chance 15+ min late Riskiest AS 646 SMF 18:51 → SEA 20:46 · 50% chance 15+ min late

Every nonstop on Sun, Oct 11

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.


WN 3980 Southwest	SMF 06:30	SEA 08:28	9%	3%	0.6%	no record
AS 1358 Alaska Flight history →	SMF 06:02	SEA 07:56	12%	3%	0.8%	78%
DL 3881 Delta flown by SkyWest Flight history →	SMF 11:34	SEA 13:45	17%	7%	0.9%	90%
DL 4125 Delta flown by SkyWest Flight history →	SMF 13:00	SEA 15:09	18%	7%	0.8%	93%worse than usual
AS 1365 Alaska Flight history →	SMF 11:13	SEA 13:09	25%	5%	0.8%	86%worse than usual
DL 4075 Delta flown by SkyWest Flight history →	SMF 07:53	SEA 10:05	26%	7%	0.7%	89%worse than usual
AS 458 Alaska	SMF 07:30	SEA 09:26	27%	5%	0.7%	no record
WN 3974 Southwest	SMF 22:05	SEA 00:02	29%	10%	0.7%	no record
DL 4153 Delta flown by SkyWest Flight history →	SMF 17:20	SEA 19:25	30%	10%	0.9%	85%worse than usual
DL 4043 Delta flown by SkyWest Flight history →	SMF 19:41	SEA 21:57	30%	9%	0.7%	81%worse than usual
AS 763 Alaska	SMF 13:10	SEA 15:06	31%	5%	0.9%	no record
WN 1272 Southwest	SMF 14:40	SEA 16:38	38%	10%	0.7%	no record
AS 646 Alaska	SMF 18:51	SEA 20:46	50%	10%	0.8%	no record

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 Sun, Oct 11 (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