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 3103 at 05:45 is the safest bet, 10% chance of being 15+ min late; the others run 26–40%.

Safest bet that day WN 3103 MDW 05:45 → SAN 07:50 · 10% chance 15+ min late · usually 94% on time Riskiest WN 2884 MDW 21:10 → SAN 23:30 · 40% chance 15+ min late · usually 52% 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 3103 Southwest Flight history →	MDW 05:45	SAN 07:50	10%	1%	0.8%	94%
WN 4648 Southwest Flight history →	MDW 10:00	SAN 12:10	26%	4%	0.7%	58%
WN 2883 Southwest Flight history →	MDW 14:15	SAN 16:25	31%	6%	0.7%	23%
WN 2884 Southwest Flight history →	MDW 21:10	SAN 23:30	40%	8%	0.7%	52%

Alternatives with one stop that day

All connections →


Southwest Details →	MDW 05:20 → PHX 06:55WN 2858	1h 00m Phoenix	PHX 07:55 → SAN 09:10WN 2771	5h 50m	96%	79%
Southwest Details →	MDW 16:05 → MCI 17:30WN 2812	1h 00m Kansas City	MCI 18:30 → SAN 19:50WN 4457	5h 45m	79%	48%

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