Today: only flights still to leave (it’s 1:22 pm at Sacramento); 3 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: 28%). Best bet: Southwest via Denver, leaving 14:15, 27% on time.

Nonstops today


WN 3802 Southwest Flight history →	SMF 23:50	MDW 05:45	18%	4%	0.1%	91%

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


Southwest Details →	SMF 19:00 → ONT 20:20WN 480	3h 35m Ontario	ONT 23:55 → MDW 05:40 +1WN 3153	8h 40m	100%	83%
Southwest Details →	SMF 18:50 → PDX 20:20WN 3813	3h 16m Portland	PDX 23:36 → MDW 05:41 +1WN 3320	8h 51m	99%	82%
Southwest Details →	SMF 17:25 → SAN 18:55WN 4774	3h 45m San Diego	SAN 22:40 → MDW 04:40 +1WN 560	9h 15m	96%	58%
Southwest Details →	SMF 18:10 → SAN 19:40WN 3509	3h 01m San Diego	SAN 22:41 → MDW 04:40 +1WN 1565	8h 30m	96%	58%
Southwest Details →	SMF 13:30 → STL 19:10WN 920	2h 41m St Louis	STL 21:51 → MDW 23:06WN 4099	7h 36m	100%	56%
Southwest Details →	SMF 14:15 → DEN 17:35WN 4105	2h 48m Denver	DEN 20:23 → MDW 23:46WN 3047	7h 31m	98%	52%
Southwest Details →	SMF 15:15 → DAL 20:40WN 3772	1h 16m Dallas	DAL 21:56 → MDW 00:14 +1WN 161	6h 59m	79%	48%
Southwest Details →	SMF 19:15 → SEA 21:10WN 555	1h 55m Seattle	SEA 23:05 → MDW 05:00 +1WN 2304	7h 45m	92%	47%
Tight connection: often missed
Southwest Details →	SMF 21:40 → ONT 23:00WN 4984	55m Ontario	ONT 23:55 → MDW 05:40 +1WN 3153	6h 00m	59%	49%
Southwest Details →	SMF 19:50 → SAN 21:20WN 4293	1h 20m San Diego	SAN 22:40 → MDW 04:40 +1WN 560	6h 50m	58%	35%
Southwest Details →	SMF 14:15 → DEN 17:35WN 4105	56m Denver	DEN 18:31 → MDW 21:55WN 2775	5h 40m	52%	27%

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