Area Forecast Discussion
Issued by NWS San Juan, PR
Issued by NWS San Juan, PR
432 FXCA62 TJSJ 010904 AFDSJU Area Forecast Discussion National Weather Service San Juan PR 504 AM AST Mon Jul 1 2024 .SYNOPSIS... Hot conditions will prevail across the islands today due to an area of drier air and stable conditions ahead of Hurricane Beryl. At this time, Hurricane Beryl should remain well south of the local islands at about 200 nautical miles. However, as the system progresses over the Caribbean waters the outer bands of Beryl will bring periods of showers and thunderstorms and breezy to windy conditions. The National Hurricane Center is monitoring Invest 96L located in the Central Atlantic. Indirect impacts could affect the local area by Thursday onwards. && .SHORT TERM...Today through Wednesday... Fair weather conditions prevailed overnight as a Saharan Air Layer with drier air and Saharan dust continued over the local area. Minimum temperatures ranged from the upper 60s to mid-70s across the higher elevations and from the upper 70s to low 80s across coastal municipalities. Winds were up to 10 mph from the east, with gusts around 20 mph across coastal areas. Breezy conditions and hazy skies will prevail throughout the day across the islands. Another hot day is expected, and a Heat Advisory (NPWSJU) is in effect for the north, west, and east sections of PR, Vieques, Culebra, and St. Croix. However, the weather conditions could quickly deteriorate later this afternoon across portions of the Anegada Passage, the Caribbean waters, and the U.S. Virgin Islands as the outer bands from Major Hurricane Beryl begin to move over the region. Beryl should pass about 200 miles or more south of the islands through Tuesday morning. In its path, the outer bands of Beryl will bring periods of thunderstorms and breezy to windy conditions, with winds ranging between 25-30 mph with stronger gusts. Quick-moving showers with periods of heavy rainfall could lead to urban and small-stream flooding and localized flash flooding. Due to the fast-moving nature of these showers, rainfall accumulations should generally range between 1 and 2 inches with isolated higher amounts, mainly across the USVI and the eastern and southern half of PR. Beryl will also bring hazardous seas and life- threatening rip currents with high surf conditions across all the islands. Weather conditions will improve by late Tuesday and continue through Wednesday as another Saharan Air Layer with drier air and suspended dust moves from the east. Therefore, hazy skies and limited shower activity can be expected through Wednesday afternoon. .LONG TERM...Thursday through Monday... No major changes have been introduced since the last discussion, and the forecast continues on track. The National Hurricane Center (NHC) continues to monitor an area of low pressure (Invest 96L) located in the Central Tropical Atlantic with a medium to high formation chance over the next few days. This low pressure is expected to approach the Caribbean waters by Thursday, and staying well south of the local area. At this moment, model guidance suggest that this system could bring a broad moisture field toward the northeastern Caribbean. Therefore, enhancing the shower and thunderstorm potential across the local islands. The precipitable water content analysis suggests between 2.25 to 2.30 inches. Therefore, a wet and unstable weather pattern will be present through at least Saturday. By Saturday, as the Invest 96L moves toward the western Caribbean drier air will filter across the region and fair weather will establish with limited shower activity. A vigorous tropical wave located behind Invest 96L is forecast to approach the local area by early Monday. This wave will bring sufficient moisture to enhance showers and thunderstorms over the local area. Model guidance does not develop this wave, however, the effects of this wave will affect the area through midweek. Regardless of the expected tropical activity, warm temperatures will dominate throughout the week. Daytime temperatures will remain in the range from the upper 80s to lower 90s along the urban and coastal sectors, and heat indices reaching the low to mid 100s. Heat Advisories are likely with the expected conditions. && .AVIATION... (06Z TAFS) Mainly VFR conditions expected across all terminals through most of the fcst period. HZ due to Saharan dust will diminish today. Conditions will gradually change from late this afternoon through Tuesday morning due to SHRA/TSRA associated with the rainbands from Hurricane Beryl. Therefore, MVFR conds are possible across the USVI terminals btw 01/21z-02/12z, and across the PR terminals btw 02/03z- 18z. East winds increasing at 15-20 kt with stronger gusts. && .MARINE... The strong surface high pressure across the Central Atlantic will continue to promote moderate to locally fresh easterly winds over the islands. The latest National Hurricane Forecast trajectory moves Major Hurricane Beryl far to the south of the regional waters late tonight into Tuesday, deteriorating marine and coastal conditions considerably, especially for the Caribbean Waters and Passages. The outer bands of Beryl may produce squally weather during that time. && .BEACH FORECAST... Swells from Beryl will create life-threatening rip currents along the south-facing beaches of Puerto Rico and the U.S. Virgin Islands from today through midweek. High surf along coasts with southern exposure are likely beginning this evening. && .SJU WATCHES/WARNINGS/ADVISORIES... PR...Heat Advisory from 10 AM this morning to 4 PM AST this afternoon for PRZ001-003-005-007-008-010>013. High Rip Current Risk through Tuesday afternoon for PRZ003-007- 011>013. High Surf Advisory from 6 PM this evening to 6 PM AST Tuesday for PRZ003-007-011. VI...Heat Advisory from 10 AM this morning to 4 PM AST this afternoon for VIZ002. High Rip Current Risk through Tuesday afternoon for VIZ001-002. High Surf Advisory from 6 PM this evening to 6 PM AST Tuesday for VIZ002. AM...Small Craft Advisory from 6 AM to 6 PM AST Tuesday for AMZ711- 726-745. Small Craft Advisory from noon today to 6 PM AST Tuesday for AMZ723. Small Craft Advisory from 6 PM this evening to noon AST Wednesday for AMZ733-741. Small Craft Advisory from 6 PM this evening to 6 PM AST Tuesday for AMZ735. && $$ SHORT TERM...DSR LONG TERM....GRS PUBLIC DESK...CVB