Sunday, October 11 · typical odds for a Sunday (too early for a weather forecast) · issued Mon 12:00 AM ET · connections flying that day

Sun, Oct 11: WN 3448 at 09:55 is the safest bet, 25% chance of being 15+ min late; the others run 36%.

Nonstops that day

All 2 nonstops →


WN 3448 Southwest	SFO 09:55	MDW 16:00	25%	8%	4.8%	no record
WN 3782 Southwest	SFO 23:40	MDW 05:47	36%	7%	1.0%	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 2 h ahead of San Francisco). Layovers up to 4 hours. Pick a connection for its 12-month details.


Delta Details →	SFO 06:00 → ATL 13:44DL 570	1h 31m Atlanta	ATL 15:15 → MDW 16:15DL 1728	8h 15m	94%	69%
Delta Details →	SFO 11:38 → ATL 19:27DL 693	1h 48m Atlanta	ATL 21:15 → MDW 22:15DL 1076	8h 37m	93%	67%

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 Sun, Oct 11 (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