Southern Puerto Rico out 10nm Marine Forecast
|Today...East Winds 10 To 15 Knots. Seas 1 To 3 Feet. Dominant Period 6 Seconds. Isolated Showers. Isolated Thunderstorms This Afternoon.|
|Tonight...East Winds 5 To 10 Knots. Seas 1 To 3 Feet. Dominant Period 6 Seconds. Isolated Showers With Isolated Thunderstorms.|
|Thursday...East Winds 5 To 10 Knots. Seas 1 To 3 Feet. Dominant Period 6 Seconds. Scattered Showers With Isolated Thunderstorms.|
|Thursday Night...East Winds 5 To 10 Knots. Seas 1 To 3 Feet. Dominant Period 6 Seconds. Scattered Showers With Isolated Thunderstorms.|
|Friday...Southeast Winds 5 To 10 Knots. Seas Around 2 Feet Or Less. Dominant Period 6 Seconds. Numerous Showers With Isolated Thunderstorms.|
|Saturday...Southeast Winds 5 To 10 Knots. Seas 1 To 3 Feet. Dominant Period 6 Seconds. Isolated Thunderstorms Through The Day. Scattered Showers.|
|Sunday...East Winds 5 To 10 Knots. Seas 1 To 3 Feet. Dominant Period 6 Seconds. Isolated Showers. Isolated Thunderstorms Through The Night.|
| Area Forecast Discussion|
National Weather Service San Juan PR
944pm AST Tuesday September 27 2022
A strong Tropical Upper Tropospheric Trough (TUTT) will move over the region during the next few days enhancing passing showers and afternoon convective development. A northerly swell remains present in the local waters tonight and is expected to diminish over the next few days. A wet pattern is forecast for the long term period as moisture from the ITCZ (Intertropical Convergence Zone) will be pulled over the northeastern Caribbean. The greatest threats remain to be the risk of excessive rainfall across central to western Puerto Rico during afternoon hours and a high risk of rip currents for the northern coastlines of Puerto Rico and the USVI.
.SHORT TERM...Tonight through Thursday... Lingering storms over the western waters of Puerto Rico are expected for this evening, with passing showers affecting the eastern sections of Puerto Rico and the USVI. A strong Tropical Upper Tropospheric Trough (TUTT) will exist northeast of the region overnight. Precipitable water values are expected to drop slightly to normal values, however this instability aloft will support passing showers with an occasional thunderstorm across eastern regions and the local waters. High pressure building across the northern Atlantic will support mainly easterly winds to prevail, with moderate speeds, causing any shower activity to be short lived. Overnight temperatures will range to the high 70s across coastal regions down to the high 60s across higher elevations.
Similar conditions will remain present tomorrow into Thursday as the TUTT-low moves to the west over the region. Moisture values look to be around the climatological normal, however with diurnal heating and local effects, active weather is expected especially for western Puerto Rico and downwind of the USVI and El Yunque during the afternoon hours. Passing showers will affect the islands throughout the day and night. The risk of flooding will be elevated across various sections of Puerto Rico, stretching from the San Juan Metro Area to the western coastline. Ponding of water across urban areas to small stream flooding is possible for affected areas. High temperatures are expected to raise into the high 80s to low 90s with some heat indices reaching in the 100s across coastal regions.
Issued at 932pm AST Tuesday September 27 2022
Seas will be generally up to 5 feet and winds up to 15 knots overnight. However, winds could be locally higher, or for brief periods. That said, sustained winds could be up to 20 knots across the Mona Passage. High risk of rip currents tonight across northern PR, Culebra, and the northern USVI. Moderate risk for St Croix, Vieques, and western PR.
.SJU WATCHES/WARNINGS/ADVISORIES... PR...High Rip Current Risk until 6am AST Wednesday for PRZ001-002- 005-008-012.
VI...High Rip Current Risk until 6am AST Wednesday for VIZ001.