Monday, October 12 · typical odds for a Monday (too early for a weather forecast) · issued Tue 12:00 AM ET · 8 nonstops

Mon, Oct 12: DL 830 at 08:15 is the safest bet, 10% chance of being 15+ min late; evening flights run 22–26%.

Safest bet that day DL 830 ATL 08:15 → SLC 10:14 · 10% chance 15+ min late · usually 89% on time Riskiest DL 653 ATL 17:55 → SLC 19:56 · 26% chance 15+ min late · usually 80% on time

Every nonstop on Mon, Oct 12

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.


DL 830 Delta Flight history →	ATL 08:15	SLC 10:14	10%	2%	0.7%	89%
DL 387 Delta Flight history →	ATL 10:10	SLC 12:10	11%	2%	0.7%	92%
DL 663 Delta Flight history →	ATL 11:56	SLC 13:50	13%	2%	0.7%	88%
DL 423 Delta Flight history →	ATL 13:55	SLC 15:51	16%	3%	0.7%	86%
DL 526 Delta Flight history →	ATL 15:20	SLC 17:18	21%	3%	0.7%	82%
DL 453 Delta Flight history →	ATL 22:03	SLC 00:08	22%	5%	0.7%	75%
DL 660 Delta Flight history →	ATL 18:59	SLC 21:05	25%	6%	0.9%	76%
DL 653 Delta Flight history →	ATL 17:55	SLC 19:56	26%	5%	0.9%	80%

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 Mon, Oct 12 (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