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 3894 at 05:50 is the safest bet, 3% chance of being 15+ min late; evening flights run 25–26%.

Safest bet that day WN 3894 STL 05:50 → BWI 08:55 · 3% chance 15+ min late · usually 92% on time Riskiest WN 3897 STL 20:10 → BWI 23:15 · 26% chance 15+ min late · usually 43% 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 3894 Southwest Flight history →	STL 05:50	BWI 08:55	3%	1%	0.6%	92%
WN 4614 Southwest Flight history →	STL 11:00	BWI 14:05	12%	2%	0.6%	76%
WN 793 Southwest Flight history →	STL 17:20	BWI 20:25	25%	6%	0.6%	78%
WN 3897 Southwest Flight history →	STL 20:10	BWI 23:15	26%	6%	0.6%	43%

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