Today: only flights still to leave (it’s 2:59 pm at Chicago); 2 already left

Sunday, October 4 · our forecast odds · issued Sun 2:00 PM ET · connections flying that day

Today looks rough: weather pushes the legs’ average chance of arriving 15+ min late to 44% (calm day: 32%). Best bet: Southwest via Las Vegas, leaving 16:10, 34% on time.

Nonstops today


WN 1940 Southwest	MDW 21:21	SJC 23:59	35%	9%	0.1%	no record

Best connections today, one ticket

Most reliable Quickest (80%+ on time)

Ranked by chance you reach San Jose on time, from each leg’s forecast for the day. Total trip = scheduled departure to arrival (San Jose is 2 h behind Chicago). Layovers up to 4 hours. Pick a connection for its 12-month details.


Southwest Details →	MDW 16:10 → LAS 18:00WN 2795	3h 35m Las Vegas	LAS 21:35 → SJC 23:10WN 2350	9h 00m	100%	65%
Southwest Details →	MDW 18:30 → LAX 20:50WN 188	1h 45m Los Angeles	LAX 22:35 → SJC 23:55WN 3222	7h 25m	83%	46%
Southwest Details →	MDW 18:30 → PHX 20:10WN 2862	1h 50m Phoenix	PHX 22:00 → SJC 23:55WN 255	7h 25m	87%	43%
Southwest Details →	MDW 15:25 → DEN 17:00WN 2769	2h 10m Denver	DEN 19:10 → SJC 20:45WN 1727	7h 20m	85%	38%
Tight connection: often missed
Southwest Details →	MDW 16:10 → LAS 18:00WN 2795	55m Las Vegas	LAS 18:55 → SJC 20:25WN 3865	6h 15m	56%	30%
Southwest Details →	MDW 18:30 → PHX 20:10WN 2862	56m Phoenix	PHX 21:06 → SJC 23:07WN 2468	6h 37m	51%	26%
Southwest Details →	MDW 18:10 → AUS 20:45WN 3171	1h 01m Austin	AUS 21:46 → SJC 23:27WN 2798	7h 17m	42%	13%

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