Saturday, October 10 · typical odds for a Saturday (too early for a weather forecast) · issued Sun 8:00 PM ET · connections flying that day

Sat, Oct 10: WN 3519 at 08:53 is the safest bet, 4% chance of being 15+ min late; the others run 15%.

Nonstops that day

All 2 nonstops →


WN 3519 Southwest	PIT 08:53	MDW 09:35	4%	1%	0.6%	no record
WN 3520 Southwest	PIT 17:18	MDW 18:00	15%	4%	0.6%	no record

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


Delta Details →	PIT 05:43 → ATL 07:26DL 1504	2h 14m Atlanta	ATL 09:40 → MDW 10:42DL 2417	5h 59m	99%	87%
Delta Details →	PIT 11:22 → ATL 13:05DL 1363	1h 24m Atlanta	ATL 14:29 → MDW 15:30DL 1728	5h 08m	97%	82%
Delta Details →	PIT 18:21 → ATL 20:13DL 1568	1h 02m Atlanta	ATL 21:15 → MDW 22:15DL 1076	4h 54m	89%	71%
Delta Details →	PIT 06:30 → DTW 07:44DL 5319 · flown by Endeavor	1h 06m Detroit	DTW 08:50 → MDW 09:14DL 4684 · flown by Endeavor	3h 44m	88%	62%
Delta Details →	PIT 11:40 → MSP 12:55DL 845	3h 43m Minneapolis	MSP 16:38 → MDW 18:18DL 4714 · flown by Endeavor	7h 37m	99%	58%

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 Sat, Oct 10 (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