textproduct: San Juan

KEY MESSAGES

Issued at 459 AM AST Thu Jan 22 2026

* A surface trough moving westward across the region from today into Friday will gradually deteriorate weather conditions, increasing the potential for showers and isolated thunderstorms.

* Choppy to rough seas and life-threatening rip currents will result in hazardous conditions for small craft and beachgoers. Small Craft Advisories and High Rip Current Statements will remain in effect through at least late Friday night.

* Breezy to windy conditions will continue today and tonight, which could cause outdoor items to be blown around or damaged.

Short Term(Today through Saturday)

Issued at 459 AM AST Thu Jan 22 2026

During the overnight hours, radar and satellite imagery showed a variable weather pattern across the islands. From late evening through the early morning hours, shower activity driven by moderately strong winds resulted in periods of showers, mainly across the local waters and portions of the northern coastal sections of Puerto Rico. Although the showers were light to moderate, rainfall accumulations were insignificant because they moved quickly under breezy to windy conditions. Gusty winds were observed in the vicinity of the showers. According to unofficial stations, parts of the San Juan metropolitan area reported wind gusts ranging from 29 to 36 mph, with sustained winds up to 21 mph. Overnight low temperatures ranged from the mid to upper 70s across coastal areas to the low 60s across the interior.

A surface high pressure system extending from the central Atlantic into the Caribbean Basin will continue to result in moderate to locally strong winds, with sustained speeds between 15 and 20 mph. Under this pattern, the islands will remain under breezy to windy conditions, with wind gusts reaching up to 30 knots, especially near the heavier showers and across coastal sections of the islands. This pattern is expected to prevail mainly during the morning hours as an induced surface trough moves into the region, accompanied by a moisture field with precipitable water values of 1.5 to 1.7 inches, which are above climatological normals for this time of year. In combination with the increased moisture, marginally cooler mid-level temperatures, and some upper-level divergence, this will be sufficient to generate showers across the islands and one or two isolated thunderstorms. The focus of the shower activity is expected to be over the eastern sections of the islands during the morning hours, followed by shower development across the western interior later in the day. Rainfall accumulations today are not expected to be significant due to the windy conditions; however, the frequency of showers may be sufficient to cause ponding in low-lying and poorly drained areas. On late today into Friday, as the induced surface trough and the associated moisture field move into the area, winds are forecast to weaken, becoming more from the east up to 15 knots. The evolving conditions will allow similar weather on Friday, with frequent light to moderate showers and occasionally stronger showers in the afternoon.

By Saturday, the pattern is expected to evolve toward somewhat drier low-level conditions, resulting in a gradual decrease in moisture content and a reduction in shower coverage. As a result, rainfall will be mainly isolated and short-lived, driven by easterly winds. Local effects, such as daytime heating and terrain interactions, may still favor the development of a few isolated showers, particularly across the interior and leeward sections. Overall, a variable but mostly typical weather pattern for this time of year is anticipated, with no significant signals of organized deep convection or meaningful hydrometeorological impacts.

Long Term(Sunday through Thursday)

Issued at 459 AM AST Thu Jan 22 2026

Improved weather conditions are forecast to start the next week as the moisture field from the surface troughs will be west of the region by early Sunday and drier air advects over the islands. Patches of drier and moist air will then result in seasonal (<1.50 in) to below seasonal (<1.20 in) PWAT values over the area. Current model guidance suggests that the most ample patches of drier air will reach the area on Sunday and Thursday, but uncertainty remains. A series of high pressure systems and frontal lows will move over the Atlantic during the period, resulting in generally easterly flow with variations of ESE and ENE flow, possibly on Wednesday and Thursday, respectively. This will steer passing showers over windward areas, particularly during the morning and overnight hours. Most available moisture will be limited to below 800 mb. Subsidence in the mid-to-upper levels of the atmosphere will inhibit shower development; however, localized effects may still induce convective showers, though no flooding is anticipated. Model guidance suggests that an upper trough will move east of the region on Monday providing some instability. 925 mb temperatures will remain at seasonal values with overnight patchy fog also forecast over areas of the interior.

AVIATION

(06Z TAFS) Issued at 459 AM AST Thu Jan 22 2026

Mostly VFR conditions will remain across all TAF sites during the day. During the period, some VCSH to SHRA would result in brief MVFR conditions across TIST, TISX & TJSJ; however, some VCSH to SHRA would result in lower Cigs and a reduction in VIS across some interior sections and across TJSJ & TJBQ. Winds will continue from the E up to 10 knots, increasing up to 15 knots and gusty winds from 22/13Z. More cloudiness is forecast from 23/00Z as a moisture field from an induced surface trough moves near the area.

MARINE

Issued at 459 AM AST Thu Jan 22 2026

A broad surface high pressure over the central Atlantic will promote fresh to locally strong easterlies today and tonight which will in turn deteriorate marine conditions, before weakening and resulting in more moderate to fresh easterly flow for the rest of the week. Small Craft Advisories will remain in effect through at least the rest of the workweek. A surface trough will move across the Northeast Caribbean today, affecting the region through Saturday and increasing shower frequency. A northerly swell is also forecast to arrive by late Monday night.

BEACH FORECAST

Issued at 459 AM AST Thu Jan 22 2026

A high risk of rip currents remains in effect across the northern and east coasts of Puerto Rico, as well as for Culebra, and the U.S. Virgin Islands, due to hazardous conditions with breaking waves up to 6 to locally 7 feet. Breezy to locally windy conditions can also result in unsecured objects being blown around. Residents and visitors are urged to continue following the warning flag system and to favor beaches with lower rip current risk, such as those along Puerto Rico's western and southern coasts. Up to a high risk of rip currents is likely to continue through the rest of the week. For the western and southern coastal areas, where the risk remains moderate, beachgoers can still expect breezy to locally windy conditions to continue, which may still result in unsecured objects being blown around, particularly in the most exposed locations.

SJU WATCHES/WARNINGS/ADVISORIES

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

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

AM...Small Craft Advisory until 6 AM AST Saturday for AMZ711.

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

Small Craft Advisory until 6 AM AST Friday for AMZ716-726-733- 741.

Small Craft Advisory until 6 PM AST this evening for AMZ735.