Friday, October 9 · typical odds for a Friday (too early for a weather forecast) · issued Mon 12:00 PM ET · connections flying that day

Fri, Oct 9: F9 3306 at 10:49 is the safest bet, 21% chance of being 15+ min late; the others run 33%.

Nonstops that day

All 2 nonstops →


F9 3306 Frontier Flight history →	JAX 10:49	SJU 14:00	21%	8%	1.8%	76%
B6 1743 JetBlue Flight history →	JAX 16:43	SJU 19:45	33%	13%	1.7%	71%

Best connections that day, one ticket

Most reliable Quickest (80%+ on time)

Ranked by chance you reach San Juan on time, from each leg’s forecast for the day. Total trip = scheduled departure to arrival. Layovers up to 4 hours. Pick a connection for its 12-month details.


Delta Details →	JAX 05:30 → ATL 06:42DL 2722	1h 23m Atlanta	ATL 08:05 → SJU 11:40DL 1757	6h 10m	98%	87%
Delta Details →	JAX 07:00 → ATL 08:15DL 2450	1h 30m Atlanta	ATL 09:45 → SJU 13:32DL 1882	6h 32m	99%	84%
American Details →	JAX 08:00 → MIA 09:20AA 3492 · flown by Envoy	1h 57m Miami	MIA 11:17 → SJU 14:12AA 2584	6h 12m	100%	83%
Delta Details →	JAX 07:05 → JFK 09:29DL 4959 · flown by Endeavor	3h 16m New York	JFK 12:45 → SJU 16:38DL 1961	9h 33m	97%	82%
Delta Details →	JAX 08:17 → ATL 09:34DL 2569	3h 26m Atlanta	ATL 13:00 → SJU 16:39DL 1946	8h 22m	99%	81%
United Details →	JAX 11:48 → IAD 13:44UA 2826	3h 40m Dulles	IAD 17:24 → SJU 21:24UA 2025	9h 36m	100%	81%
American Details →	JAX 06:18 → CLT 07:45AA 1834	3h 18m Charlotte	CLT 11:03 → SJU 14:50AA 783	8h 32m	99%	80%
United Details →	JAX 11:37 → IAH 13:11UA 4039 · flown by Mesa	1h 52m Houston	IAH 15:03 → SJU 20:38UA 701	9h 01m	97%	80%
Tight connection: often missed
JetBlue Details →	JAX 15:35 → FLL 16:54B6 1417	51m Fort Lauderdale	FLL 17:45 → SJU 20:27B6 553	4h 52m	48%	27%

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