Tuesday, October 6 · our forecast odds · issued Mon 1:00 PM ET · connections flying that day

Tomorrow: one nonstop, AA 3498 at 12:22, with a 16% chance of arriving 15+ min late.

Nonstops that day


AA 3498 American flown by Envoy Flight history →	BIL 12:22	ORD 16:17	16%	2%	0.6%	67%

Best connections that day, one ticket

Most reliable Quickest (80%+ on time)

Ranked by chance you reach Chicago on time, from each leg’s forecast for the day. Total trip = scheduled departure to arrival (Chicago is 1 h ahead of Billings). Layovers up to 4 hours. Pick a connection for its 12-month details.


Delta Details →	BIL 05:20 → SLC 06:44DL 1360	1h 06m Salt Lake City	SLC 07:50 → ORD 12:00DL 2247	5h 40m	98%	89%
United Details →	BIL 05:00 → DEN 06:53UA 5829 · flown by SkyWest	1h 07m Denver	DEN 08:00 → ORD 11:43UA 2430	5h 43m	97%	89%
Delta Details →	BIL 06:24 → MSP 09:27DL 2254	3h 58m Minneapolis	MSP 13:25 → ORD 15:05DL 1533	7h 41m	99%	88%
United Details →	BIL 06:52 → DEN 08:33UA 372	2h 42m Denver	DEN 11:15 → ORD 14:55UA 2865	7h 03m	99%	84%
American Details →	BIL 06:00 → DFW 09:55AA 3746 · flown by Envoy	2h 44m Dallas-Fort Worth	DFW 12:39 → ORD 15:12AA 1618	8h 12m	99%	84%
Delta Details →	BIL 11:50 → SLC 13:22DL 4038 · flown by SkyWest	3h 59m Salt Lake City	SLC 17:21 → ORD 21:29DL 2413	8h 39m	100%	84%
American Details →	BIL 13:12 → DFW 17:00AA 4095 · flown by Envoy	2h 36m Dallas-Fort Worth	DFW 19:36 → ORD 22:01AA 3790 · flown by Envoy	7h 49m	99%	84%
United Details →	BIL 14:25 → DEN 16:15UA 478	2h 55m Denver	DEN 19:10 → ORD 22:49UA 2258	7h 24m	99%	82%

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 Tue, Oct 6 (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