textproduct: San Juan

KEY MESSAGES

Issued at 252 AM AST Sun Mar 8 2026

* Breezy to locally windy conditions will continue across Puerto Rico and the USVI through at least midweek. Unsecured and outdoor objects may blow around.

* Fresh to strong winds will continue to result in choppy to rough seas and a high risk of rip currents across the region. Small Craft Advisories and Rip Current Statements continue in effect through at least Tuesday evening.

* A wet and unstable weather pattern will increase shower activity and the potential of isolated thunderstorms across Puerto Rico and the U.S. Virgin Islands by the first half of the workweek due to the influence of an upper-level trough.

Short Term(Today through Tuesday)

Issued at 252 AM AST Sun Mar 8 2026

Scattered showers moved across portions of eastern and northern Puerto Rico overnight, including the San Juan metropolitan area. Doppler radar estimated rainfall accumulations between 0.10 and 0.30 inches across these regions. Brief showers also passed over the U.S. Virgin Islands; however, most of this activity remained over the local waters. Overnight minimum temperatures ranged from the low to mid-70s across lower elevations and from the mid to upper 60s in higher terrain. Winds prevailed from the east at 5 to 10 mph, with occasional higher gusts.

At the surface, a strong high-pressure system will continue to dominate through midweek. Its tight pressure gradient will maintain fresh to locally strong easterly winds throughout the period. In the mid-levels, temperatures at 500 mb will remain between -8C and - 10C, supporting instability. This pattern, combined with the arrival of low-level moisture patches, will sustain a showery weather pattern. Expect passing showers to affect portions of eastern and northern Puerto Rico, Vieques, Culebra, and the U.S. Virgin Islands during the morning, followed by afternoon showers across the interior and western Puerto Rico. Precipitable water (PWAT) values will remain near or slightly above normal, around 1.50 inches, though pockets of drier air will filter in between moisture patches. The flooding risk remains limited; however, ponding of water on roads and in areas with poor drainage is possible.

From Tuesday onward, an upper-level trough extending from Jamaica and eastern Cuba, and extending toward Hispaniola will linger over the area through at least Thursday. A persistent jet aloft will support a more unstable atmospheric profile than is typical for this time of year. Temperatures at the 925 mb level are expected to remain seasonal. Highs will range from the mid-80s across lower elevations to the upper 70s and low 80s in the higher elevations each day.

Long Term(Wednesday through Sunday)

Issued at 252 AM AST Sun Mar 8 2026

At the surface, a broad high pressure system over the central Atlantic extending into the Caribbean will maintain moderate easterly winds across the region. Under this pattern, abundant patches of precipitable water with values ranging between 1.5 and 1.7 inches will continue to move across the area. At the upper levels, somewhat unfavorable weather conditions will persist with the presence of an upper-level jet of over 100 knots, enhancing vertical development and unstable conditions aloft. According to model guidance, 500 mb temperatures will range between -8 and -9 degrees Celsius. Given these conditions, from Wednesday into Thursday weather conditions will favor a showery pattern with good chances for showers. However, since surface conditions will be mostly driven by windy conditions, showers are not expected to produce significant rainfall accumulations. On Wednesday, surface winds will remain from the east; therefore, the focus of the showers will remain across eastern sections and the western interior of Puerto Rico. By Thursday, surface conditions will change slightly as winds at the 03 km layer become more southeasterly due to the interaction between the surface high pressure and a pre-frontal trough associated with a frontal boundary exiting the eastern coast of the United States.

From Friday through Sunday, mostly similar weather conditions will persist under the influence of a broad surface high pressure system over the central Atlantic, which will be reinforced as a frontal boundary pushes eastward and another high pressure system builds over the western Atlantic. Under this pattern, moderate easterly winds will continue to prevail across the region, allowing patches of moisture with precipitable water values slightly above climatological normals to move across the islands. At the upper levels, a mainly zonal flow will remain in place, generally supporting fairly stable weather conditions across the northeastern Caribbean. Given these expected conditions, the forecast calls for a typical trade wind pattern with periods of passing showers moving across the windward sections during the overnight and morning hours, followed by isolated to scattered showers developing across interior and western portions of Puerto Rico during the afternoon due to local effects and daytime heating. However, rainfall accumulations are expected to remain limited overall due to brisk winds, which promote faster-moving showers and prevent prolonged rainfall over any particular area.

AVIATION

(06Z TAFS) Issued at 252 AM AST Sun Mar 8 2026

Mainly VFR conds will prevail thru the period across all TAF sites. SHRA will continue to move into the the islands today, with VCSH affecting the PR & USVI terminals thru 08/14Z. VCSH over TJSJ/TJBQ/TIST aft 08/14Z through 08/22-3Z. E winds btwn 15-20 kt with gusts higher than 30 kt and sea breeze variations aft 08/14Z.

MARINE

Issued at 252 AM AST Sun Mar 8 2026

Fresh to locally strong east-northeasterly winds will persist throughout the forecast period, maintaining choppy to rough seas across regional waters and local passages. A Small Craft Advisory remains in effect through at least Tuesday as offshore conditions reach sustained winds of 25 knots and seas up to 8 feet. While a gradual improvement is expected across the region early next week, operators of smaller vessels are strongly urged to avoid navigating in these hazardous conditions.

BEACH FORECAST

Issued at 252 AM AST Sun Mar 8 2026

Hazardous beach conditions will persist across the region, maintaining a High Rip Current Risk through Monday for the northern and eastern shorelines of Puerto Rico, Vieques, Culebra, and the U.S. Virgin Islands. Residents and visitors are urged to monitor updates closely and strictly adhere to the guidance of beach patrols, flag systems, and posted safety signage. While a moderate risk continues elsewhere over the next several days, all beachgoers should remain vigilant, as life-threatening rip currents remain possible within the surf zone. A moderate risk is then expected to prevail across most shorelines from Tuesday onward.

SJU WATCHES/WARNINGS/ADVISORIES

PR...High Rip Current Risk through Monday morning for PRZ001-002-005- 008-012-013.

VI...High Rip Current Risk through Monday morning for VIZ001-002.

AM...Small Craft Advisory until midnight AST Tuesday night for AMZ711.

Small Craft Advisory until noon AST Monday for AMZ712-716-723- 726-733-741.