Today: WN 478 at 13:50 is the safest bet, 28% chance of being 15+ min late; evening flights run 33–39%.

Safest bet today WN 478 HOU 13:50 → BNA 15:45 · 28% chance 15+ min late · usually 36% on time Riskiest WN 2459 HOU 17:55 → BNA 19:50 · 39% chance 15+ min late

Against a calm day 35% average chance a nonstop arrives 15+ min late; 28% for the same flights on a calm-weather day

Every nonstop today

12-month record →

Ranked by the chance of arriving 15+ minutes late, 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. 6 flights that already left today are not shown.


WN 478 Southwest Flight history →	HOU 13:50	BNA 15:45	28%	5%	0.2%	36%
WN 4393 Southwest	HOU 21:05	BNA 23:05	33%	7%	0.1%	no record
WN 2014 Southwest	HOU 18:28	BNA 20:27	33%	6%	0.2%	no record
WN 4637 Southwest	HOU 14:21	BNA 16:20	35%	6%	0.2%	no record
WN 4679 Southwest	HOU 20:26	BNA 22:25	38%	6%	0.1%	no record
WN 5080 Southwest	HOU 15:45	BNA 17:40	38%	7%	0.2%	no record
WN 2459 Southwest	HOU 17:55	BNA 19:50	39%	6%	0.1%	no record

How these are worked out. Each flight’s odds are our forecast for that day; 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 4 (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