textproduct: San Juan

KEY MESSAGES

Issued at 517 AM AST Fri Jan 23 2026

* Hazardous marine and beach conditions continue, with dangerous offshore seas and rip currents posing a risk to small craft and swimmers. Marine hazards extend to Sunday afternoon while a high risk of rip currents continues through early Saturday.

* Winds are expected to ease today and Saturday, increasing again to breezy late Saturday into early Monday.

* The moisture field associated with a surface trough will continue over the area through early Sunday. Showers are expected to reach the eastern region today. In the afternoon, streamers will form west of the USVI, El Yunque, and the Cordillera Central.

Short Term(Today through Sunday)

Issued at 517 AM AST Fri Jan 23 2026

Persistent quick moving showers were observed most of the night along the eastern half of Puerto Rico, Vieques, Culebra and the Virgin Islands at times. Rainfall accumulations were not significant, however. Temperatures cooled down to the low 70s for most locations, with some areas in the interior registering values in the 60s. Skies were mostly clear along western Puerto Rico.

A surface to mid level ridge remains in place today, driving the trade winds from the east at speeds nearly 15 knots, which is lower than what it's has been observed in the past few days. At the lower levels, the moisture field associated with a surface trough will maintain precipitable water values above normal today. As a result, showers are expected to persist today. During most of the day, these showers will reach portions of eastern Puerto Rico and also the Virgin Islands. In the afternoon, the available moisture and moderate wind speeds will favor the development of streamers, forming on the westward areas of the Virgin Islands, El Yunque, and the Cordillera Central. The atmosphere is not prime for very heavy, long-lasting rain, but accumulations should be enough to have some impacts in traffic due to ponding of water and wet roads.

On Saturday, the winds will weaken 1 or 2 knots as the ridge rolls eastward and farther from the Caribbean. Other than that, in the low levels, the moisture content will remain virtually unchanged, and above normal for this time of year. It would be wise to have an umbrella or rain coat handy at all times, as brief shower interruptions are anticipated. The pattern will also favor afternoon convection once again, and while urban and small stream flooding is not very likely, there could be water surges along small streams.

On Sunday, a new surface high rolls from the west, causing an increase in winds once again, with speeds around 20 knots. The ridge will stretch into the mid levels too, while a dry air slot arrives at 850 mb. A trade wind cap inversion around this level will trap any little remaining moisture close to the surface. Therefore, the frequency of showers will decrease to nearly 10-20%, giving way to mostly sunny skies and fair weather conditions.

Long Term(Monday through Friday)

Issued at 517 AM AST Fri Jan 23 2026

A series of high pressure systems and frontal lows will move over the western to central Atlantic during the next workweek resulting in generally E to ESE steering flow. This flow will steer patches of drier and moist air towards the islands, resulting in in seasonal (<1.50 in) to below seasonal (<1.20 in) precipitable water (PWAT) values over the area. Current model guidance suggests that the most ample patches of drier air will reach the area early Monday as well as Wednesday and Thursday, but uncertainty remains. 925 mb wind speeds will remain seasonal to possibly below seasonal to end the workweek. 925 mb temperatures are now forecast to climb to above seasonal values as ESE flow brings in warmer air to the area. Model guidance suggests that an upper trough will move east of the region on Monday and Tuesday providing some instability, however it will move further east and away from the region. Subsidence in the mid-to-upper levels of the atmosphere will inhibit shower development; however, localized effects may still induce shallow convective showers, though no flooding is anticipated. Passing showers will also be steered over windward areas, particularly during the morning and overnight hours. Most available moisture will be limited to below 800 mb. Overnight patchy fog is also possible over areas of the interior.

AVIATION

(06Z TAFS) Issued at 517 AM AST Fri Jan 23 2026

Persisting SHRA expected today along TJSJ and USVI terminals early in the day. After 17Z, additional SHRA expected to develop along the Cordillera Central, reaching TJPS and TJBQ terminals. Periods of reduced VIS and low ceilings are expected. Winds will be slowing down today, but still from the E at 14-15 kts.

MARINE

Issued at 517 AM AST Fri Jan 23 2026

A broad surface high pressure over the central Atlantic will promote moderate to fresh easterlies today, deteriorating marine conditions. Small Craft Advisories will remain in effect for the offshore Atlantic through at least early Sunday. A surface trough will increase the frequency of showers through Saturday. Easterlies are forecast to increase by Sunday as another surface high builds over the Atlantic. A long period northeasterly swell is forecast to spread across the local Atlantic Waters and Caribbean Passages by around late Monday night into Tuesday.

BEACH FORECAST

Issued at 517 AM AST Fri Jan 23 2026

A high risk of rip currents remains in effect through 6 AM AST tomorrow, Saturday, for the northern and eastern beaches of Puerto Rico, Culebra, and the U.S. Virgin Islands, where life- threatening rip currents are likely. A low to moderate rip current risk will persist across mainly western and southern beaches of the islands. Under moderate areas, life threatening rip currents are possible in the surf zone. Up to a moderate risk of rip currents is forecast for the islands this weekend and into early next week. For more info, visit: weather.gov/beach/sju.

SJU WATCHES/WARNINGS/ADVISORIES

PR...High Rip Current Risk through late tonight for PRZ001-002-005- 008-012.

VI...High Rip Current Risk through late tonight for VIZ001-002.

AM...Small Craft Advisory until noon AST Sunday for AMZ711.

Small Craft Advisory until 6 PM AST this evening for AMZ712-723.