NPWSJU) issued by WFO SJU PR for additional information on the expected heat impacts. && .LONG TERM...Thursday through Monday... /from previous discussion/ Moist and unstable weather conditions are expected to continue through at least the early part of the period as a deepening upper- level trough with the axis over Hispaniola west of the region,will linger and provide good ventilation and a divergent pattern aloft. This along with good tropical moisture convergence produced by the prevailing and moderate east to southeast and a passing tropical wave, will maintain good potential for shower and thunderstorms development at least through Friday and moisture trailing the wave will combine with the instability aloft and good daytime heating to maintain moderate to high potential for afternoon and early evening convection. Based on the most recent guidance and Glvez- Davison Index (GDI)product, the potential for isolated to scattered thunderstorm will continue through Friday. Overnight and afternoon showers will be likely with a limited flood threats across portions of the islands each day. Hazy skies will continue at least through Thursday due to some lingering Saharan Dust with improving conditions by Friday and into the weekend. Over the following weekend and through Monday, a broad surface high pressure will again spread across the Central Atlantic and Eastern Atlantic result in increasing east to southeast trade winds and variable weather conditions. Under the expected low level wind flow, plenty of surface moisture will continue to stream across the islands and coastal waters, thus maintaining the potential for passing showers overnight and afternoon convection each day. This expected activity should be focused particularly across the central interior and west sections of Puerto Rico,while the U.S. Virgin Island can expect afternoon showers mainly on the west-end and downwind of the islands with fewer shower activity elsewhere from time to time. A similar and slightly above normal temperature pattern is expected to continue across the islands at least through the early part of the long term. Model guidance remains persistent in maintaining overall hot and humid conditions although the easterly are expected to increase during the latter part of the period. Residents and visitors are urged to stay informed of possible advisories or warnings due to excessive heat conditions. && .AVIATION... (18Z TAFS) Brief periods of MVFR conditions will remain possible at JSJ and JBQ in TSRA/SHRA through at least 17/22z. Aft 17/22z VFR conditions will prevail at all TAF sites. Winds are light from the E-SE, and more VRB after 17/22z. && .MARINE... Surface high pressure over the Atlantic and the proximity of an induced trough across the region will promote light to moderate east to southeast winds today through Tuesday. Passing showers and isolated thunderstorms will continue to affect the coastal waters and local passages resulting in localized hazardous marine conditions especially over the offshore Atlantic and Caribbean waters and between eastern Puerto Rico and the U.S. Virgin Islands during the early morning hours and on the west coastal areas Turin the afternoon hours. The easterly winds are forecast to increase to moderate to locally fresh by late Wednesday and through the rest of the work week. && .SJU WATCHES/WARNINGS/ADVISORIES... PR... VI... AM...None. && $$ $$