Today: DL 1378 at 19:33 is the safest bet, 23% chance of being 15+ min late; the others run 23–38%.

Safest bet today DL 1378 BNA 19:33 → SLC 22:06 · 23% chance 15+ min late Riskiest WN 4791 BNA 16:20 → SLC 18:55 · 38% chance 15+ min late · usually 49% on time

Against a calm day 28% average chance a nonstop arrives 15+ min late; 21% 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. 3 flights that already left today are not shown.


DL 1378 Delta	BNA 19:33	SLC 22:06	23%	4%	0.1%	no record
DL 2209 Delta Flight history →	BNA 19:34	SLC 22:10	23%	4%	0.1%	75%
WN 4791 Southwest Flight history →	BNA 16:20	SLC 18:55	38%	6%	0.1%	49%

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