Friday, October 9 · typical odds for a Friday (too early for a weather forecast) · issued Sun 4:00 PM ET · 3 nonstops

Fri, Oct 9: WN 3557 at 06:55 is the safest bet, 3% chance of being 15+ min late; the others run 18–24%.

Safest bet that day WN 3557 SAT 06:55 → BNA 09:10 · 3% chance 15+ min late · usually 90% on time Riskiest WN 4193 SAT 17:25 → BNA 19:40 · 24% 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 3557 Southwest Flight history →	SAT 06:55	BNA 09:10	3%	1%	0.5%	90%
WN 481 Southwest Flight history →	SAT 13:50	BNA 16:05	18%	5%	0.5%	54%
WN 4193 Southwest Flight history →	SAT 17:25	BNA 19:40	24%	8%	0.5%	27%

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