Monday, October 12 · typical odds for a Monday (too early for a weather forecast) · issued Tue 12:00 AM ET · connections flying that day

Mon, Oct 12: Delta via Atlanta, leaving 18:18, is the safest bet: 72% chance of reaching Chicago on time; the tightest one-ticket connections make it only 56% of the time.

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 behind Key West). Layovers up to 4 hours. Pick a connection for its 12-month details.


Delta Details →	EYW 18:18 → ATL 20:32DL 2168	2h 08m Atlanta	ATL 22:40 → ORD 23:53DL 1199	6h 35m	94%	72%
American Details →	EYW 17:29 → MIA 18:27AA 3895 · flown by Envoy	3h 33m Miami	MIA 22:00 → ORD 00:26 +1AA 483	7h 57m	100%	72%
American Details →	EYW 16:52 → CLT 19:10AA 3822 · flown by Envoy	3h 29m Charlotte	CLT 22:39 → ORD 23:51AA 627	7h 59m	100%	71%
Delta Details →	EYW 07:27 → ATL 09:37DL 1072	1h 45m Atlanta	ATL 11:22 → ORD 12:34DL 2894	6h 07m	92%	67%
American Details →	EYW 15:01 → DFW 16:58AA 305	3h 33m Dallas-Fort Worth	DFW 20:31 → ORD 23:04AA 3790 · flown by Envoy	9h 03m	95%	63%
Delta Details →	EYW 13:57 → ATL 16:07DL 1472	3h 30m Atlanta	ATL 19:37 → ORD 20:48DL 1139	7h 51m	100%	61%
American Details →	EYW 14:07 → CLT 16:21AA 1816	2h 05m Charlotte	CLT 18:26 → ORD 19:51AA 2488	6h 44m	89%	55%
Delta Details →	EYW 11:31 → ATL 13:42DL 1281	1h 43m Atlanta	ATL 15:25 → ORD 16:35DL 2738	6h 04m	91%	52%
Tight connection: often missed
American Details →	EYW 15:01 → DFW 16:58AA 305	50m Dallas-Fort Worth	DFW 17:48 → ORD 20:09AA 1573	6h 08m	56%	29%

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