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: B6 761 at 06:00 is the safest bet, 16% chance of being 15+ min late; the others run 17–39%.

Safest bet that day B6 761 BOS 06:00 → SJU 10:00 · 16% chance 15+ min late · usually 79% on time Riskiest B6 561 BOS 22:11 → SJU 02:11 · 39% chance 15+ min late · usually 51% 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.


B6 761 JetBlue Flight history →	BOS 06:00	SJU 10:00	16%	4%	0.7%	79%
DL 1780 Delta Flight history →	BOS 08:51	SJU 12:58	17%	4%	0.7%	78%
B6 861 JetBlue Flight history →	BOS 10:10	SJU 14:11	33%	9%	0.7%	75%
B6 561 JetBlue Flight history →	BOS 22:11	SJU 02:11	39%	14%	0.8%	51%

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