Today: WN 4881 at 12:35 is the safest bet, 21% chance of being 15+ min late; evening flights run 28–37%.

Safest bet today WN 4881 BNA 12:35 → STL 13:58 · 21% chance 15+ min late Riskiest WN 736 BNA 18:40 → STL 20:03 · 37% chance 15+ min late

Against a calm day 29% average chance a nonstop arrives 15+ min late; 19% 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. 1 flight that already left today is not shown.


WN 4881 Southwest	BNA 12:35	STL 13:58	21%	3%	0.2%	no record
WN 1371 Southwest Flight history →	BNA 13:05	STL 14:20	26%	3%	0.2%	74%
WN 682 Southwest Flight history →	BNA 21:30	STL 22:50	28%	7%	0.2%	57%
WN 770 Southwest Flight history →	BNA 18:10	STL 19:30	28%	4%	0.2%	63%
WN 2379 Southwest	BNA 22:25	STL 23:48	31%	6%	0.2%	no record
WN 736 Southwest	BNA 18:40	STL 20:03	37%	6%	0.2%	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 Mon, Oct 5 (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