Friday, October 9 · typical odds for a Friday (too early for a weather forecast) · issued Mon 12:00 PM ET · 4 nonstops

Fri, Oct 9: WN 3717 at 05:30 is the safest bet, 7% chance of being 15+ min late; the others run 11–23%.

Safest bet that day WN 3717 SJU 05:30 → BWI 09:40 · 7% chance 15+ min late · usually 88% on time Riskiest WN 3719 SJU 17:15 → BWI 21:25 · 23% chance 15+ min late · usually 84% 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 3717 Southwest Flight history →	SJU 05:30	BWI 09:40	7%	1%	0.7%	88%
WN 3718 Southwest Flight history →	SJU 10:20	BWI 14:25	11%	2%	0.6%	92%
F9 2265 Frontier Flight history →	SJU 07:34	BWI 11:40	17%	5%	1.1%	74%
WN 3719 Southwest Flight history →	SJU 17:15	BWI 21:25	23%	7%	0.7%	84%

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