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 4637 at 05:10 is the safest bet, 4% chance of being 15+ min late; evening flights run 36–37%.

Safest bet that day WN 4637 MDW 05:10 → LAX 07:25 · 4% chance 15+ min late · usually 88% on time Riskiest WN 188 MDW 18:00 → LAX 20:20 · 37% chance 15+ min late · usually 47% 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 4637 Southwest Flight history →	MDW 05:10	LAX 07:25	4%	1%	0.6%	88%
WN 2433 Southwest Flight history →	MDW 10:10	LAX 12:30	18%	3%	0.6%	73%
WN 3364 Southwest Flight history →	MDW 21:35	LAX 23:55	36%	6%	0.6%	36%
WN 188 Southwest Flight history →	MDW 18:00	LAX 20:20	37%	7%	0.6%	47%

Alternatives with one stop that day

All connections →


Southwest Details →	MDW 05:15 → DEN 06:50WN 2989	1h 00m Denver	DEN 07:50 → LAX 09:20WN 1568	6h 05m	97%	84%
Southwest Details →	MDW 06:50 → DEN 08:20WN 2765	1h 15m Denver	DEN 09:35 → LAX 11:05WN 1569	6h 15m	97%	82%
Southwest Details →	MDW 05:20 → PHX 06:55WN 2858	1h 00m Phoenix	PHX 07:55 → LAX 09:20WN 2427	6h 00m	96%	82%

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