Today: DL 1744 at 08:15 is the safest bet, 7% chance of being 15+ min late; evening flights run 12–25%.

Safest bet today DL 1744 SLC 08:15 → BOI 09:29 · 7% chance 15+ min late · usually 90% on time Riskiest DL 2920 SLC 16:37 → BOI 17:51 · 25% chance 15+ min late · usually 86% on time

Against a calm day 16% average chance a nonstop arrives 15+ min late; 13% 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.


DL 1744 Delta Flight history →	SLC 08:15	BOI 09:29	7%	2%	0.1%	90%
OO 3877 SkyWest	SLC 22:47	BOI 00:06	12%	6%	0.6%	no record
DL 2095 Delta Flight history →	SLC 11:04	BOI 12:20	13%	4%	0.1%	83%
DL 1442 Delta Flight history →	SLC 11:00	BOI 12:14	14%	4%	0.1%	93%
DL 2111 Delta Flight history →	SLC 22:50	BOI 00:05	17%	5%	0.6%	81%
DL 4446 Delta flown by SkyWest Flight history →	SLC 20:50	BOI 22:04	18%	6%	0.5%	88%
OO 4018 SkyWest	SLC 16:43	BOI 18:02	24%	6%	0.1%	no record
DL 2920 Delta Flight history →	SLC 16:37	BOI 17:51	25%	7%	0.1%	86%worse than usual

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