AFDSJU Area Forecast Discussion National Weather Service San Juan PR 1230 PM AST Sun Dec 28 2025 ...New SHORT TERM, LONG TERM, AVIATION, MARINE, BEACH FORECAST... .KEY MESSAGES... Issued at 1230 PM AST Sun Dec 28 2025 * Pulses of a long-period northerly swell will continue to arrive through midweek, maintaining a high potential for life- threatening rip currents along the north-facing beaches of Puerto Rico, including Culebra, and across the northern U.S. Virgin Islands. * Fair weather conditions will prevail through midweek, with brief passing showers at times. Late in the workweek, an upper-level trough and a weak surface trough should increase shower activity in general, though impacts are expected to be localized. * New Years Eve: Moderate (10-15 kt) east to southeast trades return. Moisture content peaks over the region, therefore, passing showers expected to increase across windward areas. && .Short Term(This afternoon through Tuesday)... Issued at 1230 PM AST Sun Dec 28 2025 The main hazard during the short-term period will be life- threatening rip currents along the northwest to northeast beaches of the islands due to pulses of long period northerly swells. Mostly sunny skies were observed across Puerto Rico and the U.S. Virgin Islands today. In general, maximum temperatures were from the low to mid 80s across the lower elevations to the low and mid 70s in the higher elevations. The wind was light with a northerly component. For tonight, fragmented low-level clouds and light showers over the Atlantic waters could reach portions of the northern USVI and northeastern PR under weak steering northerly winds. Light winds and overall dry and stable conditions are expected to continue through Tuesday, as the area remains between a weak high pressure to the west and a polar trough over the central Atlantic. Cooler than normal temperatures will continue for the rest of the period under these conditions. Global model guidance continues to indicate precipitable water content at near 0.80 inches and 925 mb temperatures at near -17C which are two standard deviations below normal levels. Therefore, minimum temperatures are expected to drop to the low 50s over the higher elevations of PR to the upper 50s and mid 60s across most lower elevations. Maximum temperatures should range from the low and mid 70s across the higher elevations to the low and mid 80s across coastal areas. && .Long Term(Wednesday through next Sunday)... Issued at 420 AM AST Sun Dec 28 2025 Expect periods of unsettled weather with brief periods of heavy rain and occasional lightning. Breezy trade winds will bring frequent passing showers, especially from Wednesday into early Thursday, with cooler-than- normal temperatures at the start of the period. Weather conditions become more active Friday into Saturday as a short-wave trough and surface-induced trough moves through the region, then gradually improve late in the weekend. Temperatures are expected to slowly warm, with warmer-than-normal conditions possible by the weekend. The main weather concerns will be rainfall, lightning, and gusty winds. The highest risk period is expected from Friday morning into Friday night, when scattered to locally numerous showers and isolated thunderstorms are likely. Lightning and brief strong wind gusts hazard risks will be more likely during this time, and trade winds will be strongest around Friday evening. From Saturday into Sunday, showers will still occur, but thunderstorm activity should gradually decrease. A lower confidence increase in thunderstorm potential may return late Sunday night, depending on how conditions evolve with the proximity of the next short- wave trough. && .AVIATION... (12Z TAFS) Issued at 1230 PM AST Sun Dec 28 2025 Mainly VFR conditions are expected to prevail across all terminals during the next 24 hours. However, -RA and SCT/BKN cigs btw FL030-FL060 are possible near TIST by 28/23z and overnight at TJSJ. Winds will continue light with a northerly component, except in weak sea/land breeze variations. && .MARINE... Issued at 1230 PM AST Sun Dec 28 2025 A weak surface high pressure over the southwestern Atlantic will promote light northeast winds across the local waters during the next few days. Meanwhile, pulses of long-period northerly swells from distant areas of low pressure will continue to spread across the Atlantic waters and passages through midweek. The swell is expected to maintain seas between 5 and 6 feet at 12 to 13 seconds through this period. Small craft are urged to exercise caution. && .BEACH FORECAST... Issued at 1230 PM AST Sun Dec 28 2025 There is a High Rip Current Risk in effect for the northwest to northeast beaches of Puerto Rico, including Culebra, and St. Thomas, and St. John in the U.S. Virgin Islands through late Monday night. However, pulses of long period northerly swells will continue to arrive through midweek. This will continue to produce life-threatening rip currents across the north-facing beaches of the islands through at least Wednesday. && .SJU WATCHES/WARNINGS/ADVISORIES... PR...High Rip Current Risk through late Monday night for PRZ001-002- 005-008-010-012. VI...High Rip Current Risk through late Monday night for VIZ001. AM...None. && $$