textproduct: San Juan

KEY MESSAGES

Issued at 224 PM AST Thu Mar 5 2026

* Patches of moisture will filter across the islands at times during the forecast period, increasing fast-moving shower frequency.

* Breezy to locally windy conditions will continue, particularly across coastal areas of the islands, unsecured and outdoor objects may blow around.

* Expect choppy to rough seas across the offshore and nearshore Atlantic and Caribbean Waters, and the local passages. Small Craft Advisories are in effect for those areas. Inexperienced mariners should avoid navigating in hazardous conditions.

* A High Risk of Rip Currents is in effect for all islands through the weekend and into early next week. Up to a moderate risk of rip currents elsewhere.

Short Term(This evening through Saturday)

Issued at 224 PM AST Thu Mar 5 2026

Todays weather was dominated by partly cloudy skies and frequent fast moving showers across Puerto Rico and the U.S. Virgin Islands. These showers produced rainfall accumulations between 0.03 and 0.50 inches across the islands. Winds remained breezy to locally windy, generally between 10 and 20 mph with higher gusts. The Automated Surface Observing System at Luis Munoz Marin International Airport reported gusts up to 33 mph. Temperatures remained in the 80s across coastal areas and in the upper 60s to lower 70s across higher elevations.

Tonight through Saturday, multiple broad surface highs across the western to central Atlantic will maintain a tight pressure gradient across the northeastern Caribbean, sustaining ENE winds between 15 and 25 mph with higher gusts, particularly across coastal areas and higher terrain. These breezy to locally windy conditions will pose a limited to elevated wind risk, as unsecured outdoor items could be blown around, and may also affect marine and coastal activities. Meanwhile, 925 mb temperatures are expected to remain near seasonal normals, supporting typical daytime temperatures across the islands.

By Friday afternoon into Saturday, model guidance indicates above- normal moisture, with precipitable water values (PWAT) increasing to around 1.50 to 1.70 inches. This increase in moisture, combined with cooler 500 mb temperatures associated with a nearby trough, will promote slightly greater atmospheric instability across the region. As a result, shower activity will become more frequent, particularly across windward areas during the overnight and morning hours, followed by afternoon convection across western and southwestern Puerto Rico. Although widespread flooding is not expected, localized urban and poor drainage flooding cannot be ruled out where showers repeatedly affect the same areas. Between these moisture patches, brief intrusions of drier air and low concentrations of Saharan dust are possible.

Long Term(Sunday through next Wednesday)

Issued at 510 AM AST Thu Mar 5 2026

High pressure over the western Atlantic will remain the dominant feature through midweek while gradually shifting northeast. This pattern will maintain easterly to east-northeasterly winds across the northeastern Caribbean, with breezy to windy conditions prevailing for much of the period. Winds may weaken slightly around midweek as the pressure gradient relaxes, though breezy conditions are still expected. Aloft, a trough over the western Atlantic and the Greater Antilles will linger nearby, with its axis initially near eastern Cuba and slowly drifting toward western Hispaniola by midweek. This feature will provide some upper-level ventilation over Puerto Rico and the U.S. Virgin Islands. Despite this, dry air in the mid-levels will continue to limit thunderstorm or deep convective development. Moisture will remain near typical to slightly above-normal levels for this time of year, before gradually trending drier later in the period. Late in the period, an easterly wind perturbation or weak surface trough may approach the area Wednesday night.

Hazards during this period will be led by breezy to windy conditions across land areas. Rainfall will remain a secondary concern, mainly from frequent fast-moving trade wind showers affecting windward areas overnight and during the morning hours. Limited afternoon showers may develop across interior and western Puerto Rico. Periods of moderate rainfall with passing showers could lead to brief ponding of water in poor drainage areas, but the overall flooding risk remains low.

AVIATION

(18Z TAFS) Issued at 224 PM AST Thu Mar 5 2026

Mainly VFR conds expected thru the period across all TAF sites. ENE winds btwn 15-20 kt with gusts 25-30 kt will continue to impact all terminals thru 05/23Z. -RA will affect TJPS at times. Periods of fast moving trade wind VCSH will continue to affect TJSJ/TISX/TIST/TJBQ through 06/12Z.

MARINE

Issued at 224 PM AST Thu Mar 5 2026

Hazardous marine conditions are expected to continue over the next several days. A series of high pressure systems across the Atlantic will promote fresh to locally strong east-northeasterly winds throughout the forecast period. The latest buoy observations show building seas between 5 and 6 feet, with winds between 20 and 22 kt and gusts up to 30 kt. This will continue to result in choppy to rough seas across most regional waters and local Caribbean passages, posing a hazard to small craft operators. At this time, Small Craft Advisories remain in effect through at least 6 PM AST Sunday, although these may be extended as hazardous conditions will possibly continue the next workweek. Inexperienced mariners, especially those operating smaller vessels, should avoid navigating in hazardous conditions.

BEACH FORECAST

Issued at 224 PM AST Thu Mar 5 2026

Some changes were introduced to the beach forecast. Hazardous beach conditions are expected to continue across the islands due to strengthening winds leading to breezy to windy conditions and a trade wind swell spreading across the local waters and passages. The latest local buoy observations showed an increase in significant wave height (between 5 and 6 feet), particularly buoys near the coastal waters of Vieques and St. Thomas. Given the current marine conditions, a Rip Current Statement is now in effect for Culebra, Vieques, St Thomas, and St. John through at least Sunday due to life- threatening rip currents possible along the surf zone. The Rip Current Statement for northern and eastern Puerto Rico and St. Croix in the U.S. Virgin Islands continues in effect through Sunday as well. Residents and visitors are encouraged to continue monitoring the conditions and to heed the advice of the flag system, as well as the beach patrol flags and posted signs. Although model guidance keeps suggesting that the swell will gradually diminish by late Friday night, hazardous conditions will like persist this weekend and early next week.

For the rest of the areas, the moderate risk will continue for the next several days. Beachgoers should exercise caution, as life- threatening rip currents are still possible along the surf zone. For additional information and location-specific rip current details, please visit: weather.gov/beach/sju.

SJU WATCHES/WARNINGS/ADVISORIES

PR...High Rip Current Risk through Sunday afternoon for PRZ001-002- 005-008-012-013.

VI...High Rip Current Risk through Sunday afternoon for VIZ001-002.

AM...Small Craft Advisory until 6 PM AST Sunday for AMZ711-712-716- 723-726-733-741.

Small Craft Advisory until 6 AM AST Friday for AMZ735.