Friday, October 9 · typical odds for a Friday (too early for a weather forecast) · issued Sun 4:00 PM ET · 5 nonstops

Fri, Oct 9: WN 4657 at 05:05 is the safest bet, 2% chance of being 15+ min late; the others run 3–13%.

Safest bet that day WN 4657 MHT 05:05 → BWI 06:40 · 2% chance 15+ min late · usually 98% on time Riskiest WN 976 MHT 17:10 → BWI 18:50 · 13% chance 15+ min late · usually 85% 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 4657 Southwest Flight history →	MHT 05:05	BWI 06:40	2%	1%	0.6%	98%
WN 2918 Southwest Flight history →	MHT 09:20	BWI 11:00	3%	2%	0.6%	98%
WN 1121 Southwest Flight history →	MHT 11:30	BWI 13:10	6%	2%	0.5%	93%
WN 868 Southwest Flight history →	MHT 13:30	BWI 15:05	10%	3%	0.6%	77%
WN 976 Southwest Flight history →	MHT 17:10	BWI 18:50	13%	6%	0.5%	85%

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