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

Fri, Oct 9: WN 3478 at 06:35 is the safest bet, 10% chance of being 15+ min late; evening flights run 15–37%.

Safest bet that day WN 3478 SAN 06:35 → BNA 12:45 · 10% chance 15+ min late · usually 84% on time Riskiest WN 3479 SAN 17:35 → BNA 23:35 · 37% chance 15+ min late · usually 27% 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 3478 Southwest Flight history →	SAN 06:35	BNA 12:45	10%	2%	0.7%	84%
WN 3480 Southwest Flight history →	SAN 22:40	BNA 04:45	15%	4%	0.8%	96%worse than usual
WN 4147 Southwest Flight history →	SAN 12:30	BNA 18:30	35%	7%	0.7%	17%
WN 3479 Southwest Flight history →	SAN 17:35	BNA 23:35	37%	10%	0.7%	27%

Alternatives with one stop that day

All connections →


Southwest Details →	SAN 06:20 → DAL 11:25WN 3906	1h 00m Dallas	DAL 12:25 → BNA 14:15WN 1275	5h 55m	94%	73%

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