Sunday, October 11 · typical odds for a Sunday (too early for a weather forecast) · issued Mon 12:00 AM ET · 7 nonstops

Sun, Oct 11: WN 4017 at 08:01 is the safest bet, 6% chance of being 15+ min late; evening flights run 21–28%.

Safest bet that day WN 4017 SNA 08:01 → SMF 09:41 · 6% chance 15+ min late Riskiest WN 4022 SNA 19:45 → SMF 21:24 · 28% 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 4017 Southwest	SNA 08:01	SMF 09:41	6%	2%	0.7%	no record
WN 4018 Southwest	SNA 09:31	SMF 11:11	11%	4%	0.7%	no record
WN 4019 Southwest	SNA 11:46	SMF 13:26	19%	5%	0.7%	no record
WN 4815 Southwest	SNA 21:20	SMF 22:55	21%	5%	0.7%	no record
WN 770 Southwest	SNA 14:10	SMF 15:50	25%	7%	0.7%	no record
WN 9008 Southwest	SNA 15:25	SMF 17:05	25%	7%	0.7%	no record
WN 4022 Southwest	SNA 19:45	SMF 21:24	28%	7%	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