698 FXCA62 TJSJ 102050 AFDSJU Area Forecast Discussion National Weather Service San Juan PR 450 PM AST Tue Oct 10 2023 .SYNOPSIS...Dry and stable weather conditions are anticipated to prevail for the next few days across the local islands. Limited shower activity is expected across the islands with little accumulations. A long period northeasterly swell continue to affect the regional waters. A rip current statement is in effect for beaches of Puerto Rico and the U.S. Virgin Islands. Please refer to the marine discussion for more details. && .SHORT TERM...Tonight through Thursday... Mainly fair weather conditions prevailed today across Puerto Rico and the U.S. Virgin Islands due to the entrance of a drier air mass into the region. This drier mass accompanied with low to moderate concentration of Saharan dust particles, promoted stable conditions and hazy skies. During the midday hours, shower activity developed across the central interior towards the western portions of Puerto Rico. However, these showers were short lived with accumulations of less than 0.50 inch. Very hot conditions were observed as well across the region with temperatures in the low to mid 90s across the coastal areas, and in the upper 80s in the interior. Heat indices reached 116 degrees in the north-central areas, where an Excessive Heat Warning was in effect. A southeasterly wind flow prevailed through much of the day. Then, later tonight winds will shift from the east. By Wednesday, dry conditions are expected once again over the area. Limited shower activity is expected, although, due to orographic effects some showers could happen along the Cordillera and western portions of Puerto Rico. Shower activity is not expected across the U.S. Virgin Islands. By late Wednesday into Thursday, moisture is expected to return. Expect an increase in shower frequency across the islands. Isolated thunderstorms cannot be ruled out with the heaviest showers. Maximum temperatures will stay in the upper 80s along the Cordillera Central and in the mid 90s across the coastal and urban areas. Heat indices and very warm to hot temperatures will continue over the area through the rest of the week. && .LONG TERM...Friday through Tuesday... High pressure at upper levels will continue over and just north of the Greater Antilles even as a TUTT develops in the western Tropical Atlantic and drops south southwest through Sunday and then west into the Caribbean Monday and Tuesday. High pressure at lower levels is present over and just north of the area through Monday, but redevelops northeast of the area on Tuesday. This will allow some moisture to filter into the area from the east northeast, but will also tend to block any strong features or the cooler air mass to the north from reaching us. Flow will weaken somewhat and turn more southeasterly Friday through Tuesday. This will allow some showers and possibly a few thunderstorms to form in the interior portions of Puerto Rico mainly due to converging winds around the island. With southeast flow returning Friday, heat indices and very warm temperatures will continue over the area with the warmest temperatures expected Friday and Tuesday. && .AVIATION...VFR conditions will prevail across local terminals. Afternoon convection may result in isolated TSRA across W-PR and near JBQ thru this evening 10/22z. Passing SHRA will increase tomorrow after 11/16z. Winds will prevail from the ESE at 10-15 kt, but locally higher due to sea breeze and near TSRA. We expect calm to light and variable winds overnight (btwn 10/23z-11/13z), then easterlies at 10 to 15 kt will return, as well as sea breeze variations. && .MARINE...Most recent CariCOOS buoy observations show seas between 3 to 5 feet across the nearshore waters. A long period northeasterly swell will continue to affect the local waters until at least Thursday, deteriorating seas across the region. For beachgoers, there is a high risk of rip currents along the northern beaches of Puerto Rico, including Culebra and Saint Croix. Conditions will start to improve by the end of the workweek. && .SJU WATCHES/WARNINGS/ADVISORIES... PR...High Rip Current Risk through Thursday afternoon for PRZ001-002- 005-008-012. VI...High Rip Current Risk through Thursday afternoon for VIZ002. AM...None. && $$ SHORT TERM...RAM LONG TERM....GRS PUBLIC DESK/UPPER AIR...LIS