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

Fri, Oct 9: AA 815 at 06:40 is the safest bet, 7% chance of being 15+ min late; evening flights run 28–36%.

Safest bet that day AA 815 MIA 06:40 → BOS 10:06 · 7% chance 15+ min late · usually 98% on time Riskiest AA 2539 MIA 20:20 → BOS 23:41 · 36% chance 15+ min late · usually 59% 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.


AA 815 American Flight history →	MIA 06:40	BOS 10:06	7%	4%	0.8%	98%
AA 1589 American Flight history →	MIA 09:26	BOS 12:57	15%	6%	0.9%	82%
AA 1565 American Flight history →	MIA 10:51	BOS 14:22	20%	10%	1.1%	83%
DL 1399 Delta Flight history →	MIA 11:30	BOS 14:59	21%	11%	1.0%	74%
AA 1538 American Flight history →	MIA 12:42	BOS 16:17	28%	16%	2.0%	72%
AA 1054 American Flight history →	MIA 21:45	BOS 00:59	28%	11%	1.2%	60%
DL 776 Delta Flight history →	MIA 19:55	BOS 23:33	32%	15%	1.1%	69%
AA 1074 American Flight history →	MIA 18:20	BOS 21:45	35%	17%	1.0%	61%
AA 2539 American Flight history →	MIA 20:20	BOS 23:41	36%	14%	1.2%	59%

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