Friday, October 9 · typical odds for a Friday (too early for a weather forecast) · issued Mon 12:00 PM ET · connections flying that day

Fri, Oct 9: one nonstop, WN 4420 at 14:40, with a 31% chance of arriving 15+ min late.

Nonstops that day

All 1 nonstop →


WN 4420 Southwest Flight history →	HOU 14:40	SLC 16:50	31%	6%	1.2%	40%

Best connections that day, one ticket

Most reliable Quickest (80%+ on time)

Ranked by chance you reach Salt Lake City on time, from each leg’s forecast for the day. Total trip = scheduled departure to arrival (Salt Lake City is 1 h behind Houston). Layovers up to 4 hours. Pick a connection for its 12-month details.


Southwest Details →	HOU 05:30 → LAS 06:30WN 3671	1h 05m Las Vegas	LAS 07:35 → SLC 10:00WN 2957	5h 30m	100%	89%
Southwest Details →	HOU 05:30 → DEN 06:55WN 1970	3h 10m Denver	DEN 10:05 → SLC 11:45WN 4027	7h 15m	100%	88%
Southwest Details →	HOU 06:25 → MDW 08:50WN 2039	1h 10m Chicago	MDW 10:00 → SLC 12:25WN 2951	7h 00m	100%	87%
Delta Details →	HOU 06:00 → ATL 09:05DL 2557	2h 51m Atlanta	ATL 11:56 → SLC 13:50DL 663	8h 50m	99%	85%
Southwest Details →	HOU 06:20 → PHX 06:55WN 2062	50m Phoenix	PHX 07:45 → SLC 10:25WN 3339	5h 05m	93%	84%
Southwest Details →	HOU 08:15 → DEN 09:45WN 1971	2h 00m Denver	DEN 11:45 → SLC 13:25WN 1731	6h 10m	99%	82%
Delta Details →	HOU 10:40 → ATL 13:46DL 1509	1h 34m Atlanta	ATL 15:20 → SLC 17:18DL 526	7h 38m	96%	77%
Southwest Details →	HOU 11:00 → BNA 12:55WN 1955	3h 25m Nashville	BNA 16:20 → SLC 18:55WN 4791	8h 55m	99%	76%
Tight connection: often missed
Southwest Details →	HOU 18:50 → MDW 21:15WN 2043	50m Chicago	MDW 22:05 → SLC 00:35 +1WN 2660	6h 45m	65%	46%
Southwest Details →	HOU 13:45 → SAN 14:55WN 4486	50m San Diego	SAN 15:45 → SLC 18:40WN 4810	5h 55m	63%	40%
Southwest Details →	HOU 18:25 → LAS 19:35WN 2003	50m Las Vegas	LAS 20:25 → SLC 22:55WN 4225	5h 30m	53%	35%

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 Fri, Oct 9 (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