Thursday, October 8 · typical odds for a Thursday (too early for a weather forecast) · issued Sun 12:00 PM ET · 3 nonstops

Thu, Oct 8: DL 859 at 06:05 is the safest bet, 8% chance of being 15+ min late; the others run 17–26%.

Safest bet that day DL 859 BOS 06:05 → SLC 09:17 · 8% chance 15+ min late · usually 89% on time Riskiest DL 445 BOS 18:45 → SLC 22:11 · 26% chance 15+ min late · usually 72% on time

Every nonstop on Thu, Oct 8

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 859 Delta Flight history →	BOS 06:05	SLC 09:17	8%	2%	0.6%	89%
DL 464 Delta Flight history →	BOS 11:15	SLC 14:20	17%	3%	0.6%	78%
DL 445 Delta Flight history →	BOS 18:45	SLC 22:11	26%	10%	0.6%	72%

Alternatives with one stop that day

All connections →


United Details →	BOS 07:45 → DEN 10:19UA 647	1h 21m Denver	DEN 11:40 → SLC 13:13UA 1963	7h 28m	96%	82%
Delta Details →	BOS 05:30 → DTW 07:38DL 1019	47m Detroit	DTW 08:25 → SLC 10:21DL 698	6h 51m	90%	82%
Delta Details →	BOS 14:52 → MSP 17:05DL 1127	1h 08m Minneapolis	MSP 18:13 → SLC 20:07DL 2607	7h 15m	90%	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 Thu, Oct 8 (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