textproduct: San Juan

KEY MESSAGES

Issued at 330 AM AST Wed Jan 7 2026

* Life-threatening rip currents are expected today and Thursday along the northwest to northeast beaches of Puerto Rico. A moderate to risk will continue along the the north and east- facing beaches of the U.S. Virgin Islands. * Drier air behind the frontal boundary will continue to filter into the area today, with few passing showers reaching Puerto Rico and the Virgin Islands, mostly during the morning and evening hours. * Seasonal temperatures are anticipated throughout the week with highs in the low to mid 80s along the lower elevations of the islands, and the mid to upper 70s in the higher mountains.

Short Term(Today through Friday)

Issued at 330 AM AST Wed Jan 7 2026

Life-threatening rip currents along the northern beaches will be the main hazard today and tomorrow.

Partly cloudy skies were observed across the islands during the overnight hours. Passing showers were noted along the northern and eastern sections of the islands, with Doppler radar estimates of half an inch of rain over Manati and San Juan. Minimum temperatures were from the upper 60s to low 70s across the lower elevations of the islands to the upper 50s and mid-60s across the higher elevations of Puerto Rico. The wind was light with a northerly component.

For the rest of the short-term period, a similar weather pattern is expected as a surface trough east of the region and east to northeasterly winds brings an influx of shallow moisture content over the area. The overall precipitable water content is expected to range between 1.20-1.40 inches, which goes from the 25th to the 50th percentile for this time of the year. At the mid-and upper-levels, a ridge is expected to slowly build from the southwestern Atlantic, promoting drier air intrusion aloft. However, only slightly warmer 500mb temperatures (around minus 7/8C) are expected, which are still within normal seasonal levels. In summary, showers are expected each day, and under light to moderate east to northeasterly trades, passing showers are expected at times along the northern and eastern sections of the islands. Shallow afternoon convection is expected to develop over portions of the Cordillera and SW PR each afternoon, where rainfall accumulations up to an inch and locally higher are possible, particularly on Thursday.

In term of temperatures, daily highs are expected to range from the mid-to upper-80s along the southern coast of PR to the low and mid- 80s across the rest of the lower elevations of the islands. Due to the expected showers and clouds at night, seasonal temperatures are expected at night, with minimums ranging from the upper 50s across the higher elevations of PR to the low 70s across coastal areas.

Long Term(Saturday through Wednesday)

Issued at 330 AM AST Wed Jan 7 2026

A strong surface high-pressure system will shift from the western to the central Atlantic during the first half of the long-term period, maintaining moderate to locally fresh east-northeast winds through midweek. The forecast remains on track as a weak surface-induced trough brings patches of moisture into the region on Saturday; however, precipitable water values will remain at normal to slightly below climatological normals, ranging between 1.15 and 1.35 inches. Despite these relatively dry conditions, the combination of east- northeast flow, daytime heating, and local effects will likely trigger afternoon showers across portions of southwestern Puerto Rico, though rainfall accumulations should remain below 1.00 inch.

By Monday and continuing through midweek, upper-level dynamics will shift as a ridge builds over the southwestern Atlantic and a Tropical Upper Tropospheric Trough (TUTT) develops over the north- central Atlantic. These features will promote drier air aloft and generally more stable conditions. Consequently, shower activity during this period will be driven primarily by the northeasterly trade winds, favoring an advective pattern that brings passing showers to the U.S. Virgin Islands and northern and eastern Puerto Rico, particularly during the overnight and early morning hours.

AVIATION

(06Z TAFS) Issued at 330 AM AST Wed Jan 7 2026

Mainly VFR conditions expected to prevail across all terminals during the next 24 hours. However, -SHRA embedded in the trades could move at times in and around TJSJ/TIST. Also, iso/sct shra and sct/bkn cigs btw FL030-FL060 are expected near TJPS btw 07/17z-21z. NE winds up to 12 kt with sea breeze variations and higher gusts expected aft 07/14z.

MARINE

Issued at 330 AM AST Wed Jan 7 2026

A long-period northeasterly swell is expected to spread across the Atlantic waters and local Caribbean passages, resulting in building seas up to 6 feet. Small craft should exercise caution under these conditions. A surface high pressure over the western Atlantic, along with weak induced surface troughs northeast of the region, will promote moderate east to northeast trade winds today through the the rest of the week.

BEACH FORECAST

Issued at 330 AM AST Wed Jan 7 2026

A long-period northerly swell will cause rough surf and life- threatening rip currents across the north-facing beaches of Puerto Rico today through at least Thursday. Elsewhere, the risk of rip currents will be moderate, except along the southern beaches of the islands where the risk will remain low throughout the week.

SJU WATCHES/WARNINGS/ADVISORIES

PR...High Rip Current Risk through Thursday afternoon for PRZ001-002- 005-008.

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