AFDSJU Area Forecast Discussion...CORRECTED National Weather Service San Juan PR 512 AM AST Thu Dec 11 2025 ...New SHORT TERM, LONG TERM, AVIATION, MARINE, BEACH FORECAST... .KEY MESSAGES... Issued at 442 AM AST Thu Dec 11 2025 * Choppy to rough seas and life-threatening rip currents are expected into the weekend. * For Puerto Rico, passing showers are expected mainly during the night/early morning hours across the eastern sections. Followed by limited afternoon shower activity over the northwest. * For the U.S. Virgin Islands, a surge in moisture moving from the Anegada Passage will bring showers and some cloudiness today. && .Short Term(Today through Saturday)... Issued at 442 AM AST Thu Dec 11 2025 Mostly fair conditions persisted during the night hours, with passing showers moving across the local waters and passages into portions of eastern Puerto Rico and the U.S. Virgin Islands. Based on station reports, rainfall accumulations remain low (up to 0.06 inches), except on St. Croix, which received 0.16 inches in 3 hours. SE winds slightly weak, but isolated stations such as in Utuado, Aibonito, and Cayey in Puerto Rico reported wind gusts up to 27 mph. In the U.S. Virgin Islands, the Cyril E. King and Henry E. Rohlsen International Airports, both at St. Thomas and St. John, respectively, reported 17-20 mph wind gusts. According to local stations, temperatures were slightly warmer compared to yesterday, with lower elevations in the low to mid 70s and higher elevations in the low to mid 60s. No major changes were introduced to the short-term forecast. The surface high pressure over the Central Atlantic will continue to promote southeasterly winds through most of the period, increasing by Saturday morning and bringing breezy to windy conditions (winds between 15 - 25 mph, wind gusts up to 35 mph) once again across the islands. The mid-level ridge lingering northeast of the region continues to dominate the weather pattern, warming mid-level temperatures, serving as a cap for deep convection and limiting cloud growth. Another drier air mass is expected to filter into the region in the morning hours, lowering the chance of precipitation across the islands. The latest HIRES models indicate afternoon convection over portions of northwestern Puerto Rico each day, though rainfall accumulations are unlikely to pose a flooding risk. Another disturbance in the trades is expected to arrive this afternoon, pooling high moisture content for this time of the year. The latest deterministic guidance of the GFS and ECMWF suggests Precipitable Water (PWAT) values increasing to seasonal and even above climatological normals (1.4 and 1.6 inches, with a low chance of reaching 1.8 inches). The most likely scenario remains, with an increase in showers over the Caribbean waters moving over southeastern and eastern portions of Puerto Rico and the U.S. Virgin Islands for the rest of the day into the night hours, persisting through Friday morning. Although a widespread flooding risk is not expected, isolated areas may experience ponding of water over roads and poorly drained areas. A similar weather pattern is expected on Friday and Saturday, with another drier air mass filtering on Friday afternoon (PWAT dropping between 1.0 and 1.2 inches) and another disturbance arriving by early Saturday, increasing once again shower activity across the islands and persisting throughout the day. && .Long Term(Sunday through Thursday)... Issued at 442 AM AST Thu Dec 11 2025 A broad surface high pressure will linger near and south of the Azores through the long term period. Meanwhile, a cold front is expected to move early in the workweek over the western Atlantic. This surface pattern will promote southeasterly winds over the local area, leading to warmer than normal daytime temperatures across the islands. Max temps are forecast to range from the upper 80s to low 90s in some of the lower elevations, with heat indices reaching the low 100s, particularly in western PR. In terms of weather conditions, a similar weather pattern is expected early in the period due to the influence of a mid-to upper-level ridge to the east/northeast of the region. This will promote fairly stable conditions, with brief patches of moisture embedded in the trades bringing passing showers across the USVI and eastern portions of PR during the night. Shallow afternoon convection is still expected to develop over NW PR, but rainfall accumulations are not expected to cause flooding concerns. However, by midweek, an upper level trough will bring SW winds aloft, and cause a brief weakness at the surface that will allow for better pooling of moisture over the area as weak surface troughs move from east to west. This will increase the chance of showers between 40-60% each day across the islands, with a slight chance of thunderstorm development over west/northwest PR late in the afternoon hours. && .AVIATION... (06Z TAFS) Issued at 442 AM AST Thu Dec 11 2025 Mainly VFR conds across most TAF sites, with brf prds of MVFR conds over TIST due to -RA through 11/13z. VCSH is expect by 11/18z due another disturbance from the SE at most terminals through at least 11/23z, reducing CIGs/VIS and brfly promoting MVFR conds. Winds from the SE btwn 10-13 kt with gusts up to 23 kt are likely after 11/13-14z, weakening btwn 5-8 kt around 11/23z. && .MARINE... Issued at 442 AM AST Thu Dec 11 2025 A surface high pressure will continue to build near the Azores through the weekend. A weak cold front and another surface high pressure will move from the western Atlantic into the central Atlantic during the next few days. This will promote moderate to locally fresh east to southeast trades across the local waters. Increasing winds and a long period northerly swell will cause choppy to rough seas, mostly over the Atlantic offshore waters. Small Craft Advisory (SCA) conditions are expected across these waters, however, SCA conditions can spread into portions of the Anegada and Caribbean waters later this weekend. && .BEACH FORECAST... Issued at 442 AM AST Thu Dec 11 2025 A long period northerly swell and increasing wind-waves will cause life-threatening rip currents along the north and east facing beaches of the islands during the next few days. There is a Rip Current Statement in effect for the northwest to northeast beaches of PR, including Culebra, and the northern USVI. Beach goers are urged to avoid swimming in these conditions, particularly today and on Friday. The west/southern beaches of the islands will have a moderate risk of rip currents. && .SJU WATCHES/WARNINGS/ADVISORIES... PR...High Rip Current Risk through late Friday night for PRZ001-002- 005-008-012. VI...High Rip Current Risk from this evening through late Friday night for VIZ001. AM...Small Craft Advisory until 6 PM AST Friday for AMZ711. && $$