Monday, October 5 · our forecast odds · issued Sun 9:00 PM ET · 8 nonstops

Tomorrow: WN 1109 at 06:15 is the safest bet, 5% chance of being 15+ min late; evening flights run 16–22%.

Safest bet that day WN 1109 BWI 06:15 → STL 07:30 · 5% chance 15+ min late · usually 91% on time Riskiest WN 1111 BWI 19:00 → STL 20:20 · 22% chance 15+ min late · usually 62% on time

Against a calm day 12% average chance a nonstop arrives 15+ min late; 12% for the same flights on a calm-weather day

Every nonstop on Mon, Oct 5

12-month record →

Ranked by the chance of arriving 15+ minutes late, 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 1109 Southwest Flight history →	BWI 06:15	STL 07:30	5%	1%	0.1%	91%
WN 1169 Southwest	BWI 06:35	STL 08:04	5%	1%	0.2%	no record
WN 1012 Southwest Flight history →	BWI 07:50	STL 09:05	8%	1%	0.2%	100%
WN 3589 Southwest	BWI 09:15	STL 10:44	9%	2%	0.1%	no record
WN 1110 Southwest Flight history →	BWI 09:35	STL 10:50	11%	2%	0.1%	83%
WN 1172 Southwest	BWI 22:00	STL 23:30	16%	5%	0.6%	no record
WN 1171 Southwest	BWI 15:55	STL 17:26	19%	5%	0.5%	no record
WN 1111 Southwest Flight history →	BWI 19:00	STL 20:20	22%	6%	0.6%	62%

How these are worked out. Each flight’s odds are our forecast for that day; 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 Mon, Oct 5 (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