textproduct: San Juan

KEY MESSAGES

Issued at 336 AM AST Sun Nov 15 2026

- Drier airmass will help reduce heat indices, but above-normal temperatures will likely continue today, mainly across coastal areas, lowlands, interior valleys, and urban zones. Sensitive individuals should stay hydrated and reduce sun exposure during peak daytime heat.

- Fair weather conditions are expected across the islands today with the presence of a dry airmass.

- Frequency of morning showers is expected to increase by Monday onward across the USVI and E PR, along with afternoon showers and isolated thunderstorm activity across W PR.

- Life-threatening rip currents remain possible (moderate risk) today across southern beaches of PR. Beach conditions should gradually improve this afternoon into Monday as winds and seas diminish. The moderate risk will return along north-exposed beaches Monday night onward.

Short Term(Today through Tuesday)

Issued at 336 AM AST Sun Nov 15 2026

Quiet weather conditions persisted overnight, as indicated by satellite and radar imagery. Only a few showers, accompanied by isolated thunderstorms, developed over the waters approximately 40 miles northwest of Puerto Rico. Surface observations recorded above-normal minimum temperatures, ranging from the upper 70s to lower 80s across coastal areas and from the 60s to 70s across mountainous regions. Light winds prevailed overnight.

A broad surface high pressure over the central Atlantic will promote south to southeast winds today. The pressure gradient is weakening, resulting in lighter winds compared to previous days. Aloft, a mid to upper-level ridge persisting over the region will maintain subsidence and dry air, suppressing significant rainfall development across the islands. Today is expected to be the most stable day of the forecast period, with the arrival of a drier air mass with precipitable water values of around 1.2 inches and slight concentrations of Saharan dust particles. Weather conditions will be dominated by periods of sunshine and warm temperatures. These conditions will likely result in above-normal temperatures, particularly across coastal areas, lowlands, interior valleys, and urban areas. Minimum temperatures are already running above normal, so the day will start on the warm side. Stay hydrated and limit sun exposure during peak heating hours.

During Monday and Tuesday, atmospheric moisture is expected to recover slightly, with precipitable water values returning to seasonal levels and relative humidity in the 850 to 700 mb layer showing some improvement. Relative humidity in the 700 to 500 mb layer will also gradually increase, indicating a modest recovery in mid- level moisture. Meanwhile, 250 mb geopotential heights and 1000 to 500 mb thickness values are expected to have relatively minor changes, suggesting limited variation in the overall atmospheric pattern. Weather conditions will be influenced by easterly disturbances bringing periodic pulses of moisture across the islands. However, the mid-level ridge will weaken slightly but will continue to promote moderate subsidence, potentially limiting deeper convective development. Overall, expect morning showers across windward sections of Puerto Rico and the U.S. Virgin Islands, followed by afternoon convection across the interior and western portions of Puerto Rico, driven by the prevailing easterly wind flow. This will bring back the possibility of observing ponding of water on roads and in poorly drained areas, also a low chance of urban and small streams flooding (Level 1 of 4 of excessive Rainfall Risk).

Long Term(Wednesday through Sunday)

Issued at 336 AM AST Sun Nov 15 2026

A seasonal weather pattern is expected for the remainder of the workweek, transitioning to more frequent passing showers and variable conditions over the weekend as additional tropical moisture filters into the region. An ESE flow will prevail through the second half of the workweek as surface high pressure remains centered across the central Atlantic, shifting more southeasterly over the weekend as an induced surface low develops north northwest of the local area. A mid- level ridge will remain in control through most of the long- term period, maintaining generally stable conditions aloft. However, trade wind perturbations induced by an upper low well east of the Caribbean (near 40W to 50W) will bring pockets of moisture from time to time, mainly confined to the lower levels of the atmosphere. Precipitable water values will fluctuate between 1.6 to 1.8 inches, which is within seasonal levels for this time of the year. Therefore, expect morning passing showers across windward areas, followed by afternoon showers and isolated thunderstorms across the interior and northwestern quadrant of Puerto Rico, as well as potentially into portions of the San Juan metropolitan area. Streamers are also likely to develop downwind from the USVI, Vieques, and Culebra. While an upper-level trough will cross the region from the west Thursday into Friday, dry mid- levels will limit convective enhancement.

Over the weekend, as a more southeasterly flow establishes and the surface low develops NNW of the region, additional moisture will pool across the islands, with precipitable water values reaching 1.8 to 2.0 inches along with above seasonal levels of moisture in the mid- level moisture. This setup will favor more frequent showers across the regional waters and windward areas, including the USVI, as well as more scattered afternoon showers and thunderstorms across the interior and northwestern quadrant of Puerto Rico. The persistent ESE to SE flow will maintain a daily heat risk, particularly for sensitive individuals. Please continue to follow recommendations from official health authorities.

AVIATION

(06Z TAFS) Issued at 336 AM AST Sun Nov 15 2026

VFR conditions are expected across all TAF sites thru the fcst period. Overall no significant wx impacts. SE to S winds around 10 to 12 kt will prevail, with sea breeze variations, becoming around lighter and vrb overnight.

MARINE

Issued at 336 AM AST Sun Nov 15 2026

A surface high pressure extending from the eastern to central Atlantic will promote light to moderate southeasterly winds across the regional waters through at least Monday. Seas will generally range between 3 and 5 feet, occasionally reaching up to 6 feet across the offshore waters and local passages. Marine conditions are expected to continue improving throughout the week as winds and wind- driven seas continue to decrease. However, passing showers and isolated thunderstorms may produce locally higher winds and seas.

BEACH FORECAST

Issued at 336 AM AST Sun Nov 15 2026

Wind-driven seas will continue to support a moderate risk of life- threatening rip currents across most beaches of Puerto Rico and the U.S. Virgin Islands through early today. The rip current risk is expected to decrease from today onwards as wind and seas continue to subside, with additional improvements anticipated through mid-week.

Despite the improving conditions, beachgoers should continue to exercise caution, particularly along exposed beaches. Life- threatening rip currents can still develop near jetties, groins, piers, and reefs, even where a low risk is forecast. Although shower and thunderstorm activity is expected to remain limited, isolated thunderstorms may develop near the western and northwestern beaches of Puerto Rico during the afternoon hours. Beachgoers should seek shelter immediately if thunder is heard and remain weather aware.

FIRE WEATHER

Issued at 336 AM AST Sun Nov 15 2026

Minimum relative humidity values are expected to decrease into the 50s across southern coastal Puerto Rico and the U.S. Virgin Islands today as a drier air mass moves across the region. However, winds are expected to remain below fire weather thresholds, helping to limit the overall fire danger.

SJU WATCHES/WARNINGS/ADVISORIES

PR...None. VI...None. AM...None.