Today: only flights still to leave (it’s 4:05 pm at San Jose); 2 already left

Sunday, October 4 · our forecast odds · issued Sun 5:00 PM ET · connections flying that day

Today looks like a normal day here: all 2 nonstops are 18–21% likely to arrive 15+ min late.

Nonstops today


WN 623 Southwest	SJC 22:55	MDW 05:00	18%	7%	0.1%	no record
WN 3824 Southwest	SJC 23:00	MDW 05:08	21%	8%	0.1%	no record

Best connections today, 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 Jose). Layovers up to 4 hours. Pick a connection for its 12-month details.


Southwest Details →	SJC 19:35 → LAX 21:00WN 3680	2h 55m Los Angeles	LAX 23:55 → MDW 05:55 +1WN 2413	8h 20m	95%	61%
Southwest Details →	SJC 17:30 → SAN 18:55WN 3702	3h 45m San Diego	SAN 22:40 → MDW 04:40 +1WN 560	9h 10m	97%	55%
Tight connection: often missed
Southwest Details →	SJC 20:00 → SAN 21:25WN 4513	1h 15m San Diego	SAN 22:40 → MDW 04:40 +1WN 1565	6h 40m	39%	22%

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 Sun, Oct 4 (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