Today: AA 2582 at 08:20 is the safest bet, 9% chance of being 15+ min late; evening flights run 22–24%.

Safest bet today AA 2582 MIA 08:20 → SJU 11:04 · 9% chance 15+ min late · usually 94% on time Riskiest F9 3378 MIA 23:30 → SJU 02:26 · 24% chance 15+ min late · usually 71% on time

Against a calm day 18% average chance a nonstop arrives 15+ min late; 19% for the same flights on a calm-weather day

Every nonstop today

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. 2 flights that already left today are not shown.


AA 2582 American Flight history →	MIA 08:20	SJU 11:04	9%	4%	0.3%	94%
AA 1341 American Flight history →	MIA 08:49	SJU 11:34	10%	4%	0.3%	86%
F9 2284 Frontier Flight history →	MIA 08:03	SJU 10:56	16%	7%	0.6%	77%
AA 1976 American	MIA 10:40	SJU 13:26	16%	4%	0.2%	no record
AA 2584 American Flight history →	MIA 11:17	SJU 14:12	18%	4%	0.2%	92%worse than usual
AA 457 American	MIA 12:57	SJU 15:42	18%	6%	0.2%	no record
AA 2581 American Flight history →	MIA 13:03	SJU 15:47	20%	5%	0.2%	82%
AA 3165 American Flight history →	MIA 15:40	SJU 18:24	20%	7%	0.3%	74%
AA 3011 American	MIA 19:28	SJU 22:16	22%	9%	0.7%	no record
AA 1364 American Flight history →	MIA 19:16	SJU 21:59	23%	8%	0.7%	66%
F9 3378 Frontier Flight history →	MIA 23:30	SJU 02:26	24%	15%	0.9%	71%

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