Friday, October 9 · typical odds for a Friday (too early for a weather forecast) · issued Sun 4:00 PM ET · 8 nonstops

Fri, Oct 9: WN 3829 at 06:10 is the safest bet, 3% chance of being 15+ min late; evening flights run 17–24%.

Safest bet that day WN 3829 SMF 06:10 → SNA 07:35 · 3% chance 15+ min late · usually 94% on time Riskiest WN 3834 SMF 18:30 → SNA 20:00 · 24% chance 15+ min late · usually 75% 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.


WN 3829 Southwest Flight history →	SMF 06:10	SNA 07:35	3%	1%	0.6%	94%
WN 3329 Southwest Flight history →	SMF 09:00	SNA 10:30	8%	2%	0.6%	96%
WN 3831 Southwest Flight history →	SMF 11:50	SNA 13:20	14%	4%	0.6%	62%
WN 2738 Southwest Flight history →	SMF 13:20	SNA 14:50	16%	4%	0.5%	80%
WN 3837 Southwest Flight history →	SMF 20:45	SNA 22:20	17%	3%	0.6%	93%worse than usual
WN 3832 Southwest Flight history →	SMF 14:50	SNA 16:20	18%	5%	0.6%	74%
WN 3833 Southwest Flight history →	SMF 15:50	SNA 17:20	19%	5%	0.6%	84%
WN 3834 Southwest Flight history →	SMF 18:30	SNA 20:00	24%	6%	0.6%	75%

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