776 FXCA62 TJSJ 112024 AFDSJU Area Forecast Discussion National Weather Service San Juan PR 424 PM AST Sat Jul 11 2020 .SYNOPSIS... Mostly fair weather condition are expected for the rest of the afternoon hours with some showers over western sections of Puerto Rico. Then, a tropical wave is expected to arrive the region and isolated to scattered showers and thunderstorms are expected over eastern sections of Puerto Rico and the U.S. Virgin Islands. On Monday, a more stable weather pattern is expected with mostly sunny skies. Marine conditions will continue choppy for at least Sunday Morning. Therefore a small craft advisories are in effect. && .SHORT TERM...Rest of today through Monday... Mostly fair weather conditions are expected through tonight due to a drier airmass over the region currently. As a tropical wave will approach the islands and surrounding waters starting tonight, scattered to numerous showers and a few thunderstorms are expected across the forecast area. The cloudiness, shower and thunderstorm potential will be intermittent tonight into Sunday. Rainfall accumulations are expected to cause urban and stream flooding over sections of the islands that will experience the most persistent and heaviest rains, particularly for portions of the San Juan metro and the eastern coastal municipalities late tonight into Sunday morning. Showers and thunderstorms may affect the USVI, but significant flooding is not expected, though ponding of water in poor drainage areas is expected. For Sunday afternoon, the moisture of the tropical wave will combine with diurnal and local effects to promote showers and isolated thunderstorms over the interior and northwestern portions of Puerto Rico. It is also worth noting that showers and thunderstorms are also expected across the local waters. Showers will diminish by sunset, and only isolated to scattered showers are possible across the islands and regional waters from time to time. By Monday, drier conditions are expected once again. Thus, limited shower activity is expected over the islands. Another round of Saharan dust will invade our area which will cause hazy skies. .LONG TERM...Tuesday through Saturday...From Prev. Discussion... Drier air with suspended Saharan dust will return next early next week and linger through Wednesday. A northeast wind flow will prevail as a broad surface high pressure holds across the central Atlantic. However, shallow moisture will move at times with the trade winds to cause passing light showers across the USVI and eastern sections of PR during the overnight and early morning hours. Followed by diurnal afternoon convection over west/southwest PR. Moisture increases during the second half of the week as a retrogressing TUTT and an induced low-level perturbation enters the eastern Caribbean and moves across the region. Therefore, shower and thunderstorm activity is expected to increase, mainly in diurnal activity over central and western PR. && .AVIATION...Aviation...VFR conds expected through the daytime hours across the local terminals, except perhaps TJBQ since SHRA/TSRA is expected near TJBQ after 11/19Z. East winds at around 15KT with occasional gusts and sea breeze variations today. An approaching tropical wave will cause an increase in cloudiness and shower activity, then VCSH/VCTS can be expected overnight across the local terminals. Winds will slightly decrease tonight, but could be gusty near the showers. && .MARINE... Choppy marine conditions will continue across most of the local waters due to seas up to 7 feet and winds up to 20 kts. Therefore, a small craft advisory is in effect over the Atlantic offshore waters of the region. Elsewhere, small craft operators are urged to exercise caution. A moderate risk of rip current for most of the local beaches, with a high risk of rip current over Cramer Park in Saint Croix. In the night hours today, a tropical wave is expected to reach the region causing showers and thunderstorms over the local waters. On Monday, marine conditions are expected to improve. && .PRELIMINARY POINT TEMPS/POPS... SJU 78 90 79 91 / 50 50 30 30 STT 80 89 82 90 / 40 30 30 30 && .SJU WATCHES/WARNINGS/ADVISORIES... PR...None. VI...High Rip Current Risk through late tonight for St Croix. AM...Small Craft Advisory from 6 AM to 8 PM AST Sunday for Anegada Passage Southward to 17N. Small Craft Advisory from 8 PM this evening to 8 PM AST Sunday for Atlantic Waters of Puerto Rico and USVI from 10 NM to 19.5N. && $$ SHORT TERM...FRG LONG TERM....99 PUBLIC DESK...LIS