textproduct: San Juan

KEY MESSAGES

Issued at 142 AM AST Sat Mar 14 2026

* Mostly sunny conditions are expected today, although a few localized showers may still filter over eastern PR and some showers developing during the afternoon hours across western Puerto Rico.

* Increasing winds are expected late today into next week, leading to hazardous marine and beach conditions.

* Across the U.S. Virgin Islands, occasional passing trade-wind showers will continue, with a drying trend expected throughout the day.

Short Term(Today through Monday)

Issued at 142 AM AST Sat Mar 14 2026

Overnight conditions remained generally tranquil across Puerto Rico and the U.S. Virgin Islands. Skies were mostly clear, with only isolated passing trade-wind showers affecting most waters and some coastal areas. Temperatures remained in the upper 60s to mid 70s along the coasts and in the 60s across higher terrains, while winds were light and variable. No hazardous weather was observed.

Today is expected to be the driest and most stable day of the short-term period, with high confidence in limited rainfall coverage. The latest guidance indicates precipitable water values falling to near the 25th percentile, accompanied by reduced mid-level humidity and slightly warmer mid-level temperatures, a combination that promotes a more stable atmospheric profile. Under this drier air mass, mostly sunny to partly cloudy skies will prevail. Only brief, shallow trade-wind showers are expected across windward sectors during the morning, with isolated afternoon development over western Puerto Rico due to local effects. The probability of measurable rainfall will remain low, and no flooding risk is anticipated. Meanwhile, easterly trade winds will strengthen as a high-pressure system builds over the western Atlantic, leading to breezy conditions by afternoon. While no significant hazards expected, occasional gusts may affect outdoor activities and marine conditions as we head into Sunday.

On Sunday, a gradual increase in moisture is expected as another patch of moisture moves into the region. Precipitable water values are forecast to rise to around 1.50 inches or near to slightly above normal values for this time of the year, which will support a higher frequency of passing showers embedded in the trades. Despite limited instability, periods of showers are likely across eastern Puerto Rico and the U.S. Virgin Islands during overnight and morning hours, followed by isolated to scattered afternoon activity over western Puerto Rico. As rainfall coverage increases, the flooding threat will rise to limited, meaning localized urban and poor-drainage flooding will be possible, particularly where showers repeatedly affect the same areas. Breezy to locally windy conditions will persist, increasing the risk of minor impacts such as blowing unsecured objects and choppy marine and coastal conditions. Residents and visitors should monitor updates, especially those planning outdoor or marine activities Sunday into early next week.

Long Term(Tuesday through Saturday)

Issued at 142 AM AST Sat Mar 14 2026

A broad high pressure will be present over the central Atlantic to start the long term period, and will result in breezy to windy E to ESE winds. Wind speeds at 925 mb will be above normal to start the period, resulting in breezy to locally windy conditions. Unsecured items could blow around. Up to an elevated wind risk is forecast to start the long term period for coastal areas. As low pressure systems move into the western Atlantic and continue displacing the broad high eastward, the pressure gradient will gradually relax over our region during the second half of the week, a limited wind risk is still forecast at least through Thursday. Winds will continue mainly from the E to ESE through the period. Mid-level atmospheric conditions are expected to remain generally stable throughout the forecast period. Model guidance indicates that 700500 mb lapse rates will be below normal to low end normal values, with 500 mb temperatures remaining near their climatological normals to slightly above normal. While an upper-level trough may develop northeast of the area during the period, its main instability will largely bypass the local region. As a result, conditions will be marginally stable, which will limit the development of deep convection and instead favor shallow trade wind showers. Despite this, the breezy to windy E to ESE flow will steer showers and shallow moisture patches toward windward areas. Shallow moisture patches arriving over the islands will keep precipitable water (PWAT) values around normal but with a general drying trend, with some variability linked to the moist and dry patches. This will result in passing showers across windward areas, particularly during the overnight and morning hours across eastern PR and the USVI. Diurnal heating, sea breeze convergence and local effects will fuel afternoon convective showers over the interior to western and northwestern PR, as well as lines of showers developing from the local islands. Although the fast steering flow will limit rainfall accumulations, ponding of water is possible on roads and in poorly drained areas. 925 mb temperatures will stay near normal but will be on a general warming trend due to less cloud cover and the E to ESE flow. Patchy fog is possible in interior sectors of PR during the overnight hours.

AVIATION

(06Z TAFS) Issued at 142 AM AST Sat Mar 14 2026

VFR condt across all TAF sites. VCSH possible at TJSJ, TIST, and TJBQ through 14/14Z. After 14/17Z VCSH will affect TJBQ, TJSJ, and TJBQ. E-NE winds btwn 10-15 kt with gusts up to 25 kt and sea breeze variations aft 14/13Z.

MARINE

Issued at 142 AM AST Sat Mar 14 2026

Today, surface high pressure building over the western and central Atlantic will result in an increasing pressure gradient, leading to moderate to locally fresh easterly winds that will strengthen further from Sunday onward. These wind-driven seas will lead to choppy to rough sea conditions across all exposed local waters from Sunday into the upcoming workweek. From Monday through midweek, fresh to strong easterly winds will make additional areas of the regional waters hazardous, with seas building to 7 to 8 feet and winds up to 25 knots with higher gusts. Small Craft Advisories are currently in effect for the offshore Atlantic waters and the Anegada Passage starting midday Sunday. The Small Craft Advisory will then extend over the offshore Caribbean waters by Monday. However, small boat operators should stay tuned for further updates, as additional Small Craft Advisories may be issued.

BEACH FORECAST

Issued at 142 AM AST Sat Mar 14 2026

There is a moderate risk of rip currents today across most of the northern exposed beaches of Puerto Rico and U.S. Virgin Islands, while a low risk persists for the southern coast. Although beach conditions will remain generally manageable for experienced swimmers, visitors are urged to exercise caution, particularly near jetties, rocks, and other structures.

From Sunday and early next week, coastal conditions are expected to deteriorate gradually. Strengthening easterly winds will generate choppy to rough seas across the regional waters, increasing wave action along exposed beaches. As a result, the risk of rip currents is expected to increase to high along many northern and eastern exposed beaches of the islands by Monday.

Beachgoers should remain alert to changing coastal conditions and continue monitoring the latest forecasts and statements. For additional information, please visit: weather.gov/beach/sju.

FIRE WEATHER

Issued at 142 AM AST Sat Mar 14 2026

Today's fire weather treat will be LOW, but localized higher fire weather conditions are possible. Winds will gradually become stronger but due to previous rains, RH values will remain near to above criteria. Regardless, drying conditions expected today. At this time an RFD will not be issued, but we encourage partners to continue monitoring conditions in the coming days, particularly by Monday.

SJU WATCHES/WARNINGS/ADVISORIES

PR...None. VI...None. AM...Small Craft Advisory from 1 PM Sunday to 2 AM AST Wednesday for AMZ711-723.

Small Craft Advisory from 6 AM Monday to 2 AM AST Wednesday for AMZ733.