Friday, October 9 · typical odds for a Friday (too early for a weather forecast) · issued Sun 4:00 PM ET · 4 nonstops

Fri, Oct 9: WN 4398 at 05:10 is the safest bet, 6% chance of being 15+ min late; evening flights run 24–34%.

Safest bet that day WN 4398 LAX 05:10 → MDW 11:10 · 6% chance 15+ min late · usually 90% on time Riskiest WN 4541 LAX 18:20 → MDW 00:20 · 34% chance 15+ min late · usually 37% on time

Every nonstop on Fri, Oct 9

12-month record →

Ranked by the chance of arriving 15+ minutes late (typical odds: the weather this date has had in past years), with each flight’s on-time record over Aug 2025 – Jul 2026 beside it. Times are local. Pick a flight for its forecast. Click a column to sort.


WN 4398 Southwest Flight history →	LAX 05:10	MDW 11:10	6%	1%	0.6%	90%
WN 2413 Southwest Flight history →	LAX 23:55	MDW 05:55	24%	5%	0.6%	86%worse than usual
WN 734 Southwest Flight history →	LAX 11:45	MDW 17:40	29%	5%	0.6%	55%
WN 4541 Southwest Flight history →	LAX 18:20	MDW 00:20	34%	8%	0.6%	37%

Alternatives with one stop that day

All connections →


Southwest Details →	LAX 05:05 → PHX 06:30WN 116	1h 00m Phoenix	PHX 07:30 → MDW 12:50WN 3296	5h 45m	97%	88%
Southwest Details →	LAX 10:15 → SLC 13:00WN 4322	1h 05m Salt Lake City	SLC 14:05 → MDW 18:05WN 3750	5h 50m	75%	56%

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