Friday, October 9 · typical odds for a Friday (too early for a weather forecast) · issued Sun 4:00 PM ET · 6 nonstops

Fri, Oct 9: WN 2900 at 07:50 is the safest bet, 5% chance of being 15+ min late; evening flights run 23–26%.

Safest bet that day WN 2900 MDW 07:50 → STL 09:10 · 5% chance 15+ min late · usually 95% on time Riskiest WN 2904 MDW 18:00 → STL 19:10 · 26% chance 15+ min late · usually 70% 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 2900 Southwest Flight history →	MDW 07:50	STL 09:10	5%	1%	0.6%	95%
WN 2901 Southwest Flight history →	MDW 11:00	STL 12:10	13%	2%	0.6%	75%
WN 2902 Southwest Flight history →	MDW 13:00	STL 14:10	14%	3%	0.6%	78%
WN 2903 Southwest Flight history →	MDW 14:45	STL 15:55	18%	4%	0.6%	62%
WN 2905 Southwest Flight history →	MDW 21:35	STL 22:55	23%	5%	0.6%	64%
WN 2904 Southwest Flight history →	MDW 18:00	STL 19:10	26%	5%	0.6%	70%

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