Atlantic from 19N to 22N between 55W and 65W Offshore Forecast
|Today...E To Se Winds 10 To 15 Kt. Seas 4 To 6 Ft.|
|Tonight...E Winds 10 To 15 Kt. Seas 4 To 6 Ft.|
|Wed...E Winds 15 To 20 Kt. Seas 4 To 6 Ft.|
|Wed Night...E Winds 10 To 15 Kt. Seas 4 To 6 Ft.|
|Thu...E Winds 10 To 15 Kt. Seas 4 To 6 Ft.|
|Thu Night...E Winds 10 To 15 Kt. Seas 4 To 6 Ft.|
|Fri...E Winds 15 Kt. Seas 4 To 6 Ft.|
|Fri Night...E Winds 15 To 20 Kt. Seas 4 To 6 Ft.|
|Sat...E To Se Winds 15 Kt. Seas 4 To 6 Ft.|
|Sat Night...E To Se Winds 15 To 20 Kt. Seas 4 To 6 Ft.|
| Area Forecast Discussion|
National Weather Service San Juan PR
1151am AST Thu July 7 2022
Isolated shower activity is affecting portions of eastern PR and the San Juan Metro. Streamers of showers are expected into the afternoon hours, likely developing thunderstorms. This means that some areas of the SJ metro as well as west/northwest PR can expect thunderstorms this afternoon, while isolated to scattered showers are forecast elsewhere. Urban and small stream flooding is possible this afternoon with in areas with the heaviest rainfall.
Seas up to 5 feet and winds up to 20 knots expected today, seas increasing up to 6 feet tonight. Therefore, small craft operators are urged to exercise caution. There is a high risk of rip currents across the beaches of north central and northwestern PR, while most other beaches will have a moderate risk, including the USVI beaches.
/issued 508am AST Thu July 7 2022/
SYNOPSIS... Another round of showers and thunderstorms are expected for each afternoon this week across western Puerto Rico, and also downstream from El Yunque and from the Virgin Islands. Urban and small stream flooding will be possible with this activity. Temperatures are expected to increase to the low 90s with heat indices just above 100 degrees.
SHORT TERM...Today through Saturday... This morning, conditions will remain calm, with the skies mostly clear to partly cloudy, mainly due to overnight rains across the Virgin Islands and most of Puerto Rico. Therefore, expect a mixture of sunshine and clouds. However, the east south-easterly winds will sometimes push a few clouds and showers across eastern PR.
A Tropical Upper Tropospheric Trough (TUTT) lingering near the islands will provide favorable environmental conditions (good dynamic aloft) for the next few days. The instability combined with diurnal heating, local effects, and sea breeze variations will result in afternoon showers and thunderstorms over the interior and western PR and downwind from the Virgin Islands and El Yunque. El Yunque streamer could produce periods of moderate to heavy showers across the San Juan Metropolitan area. This activity could result in urban and small stream flooding. Under an east-southeast wind flow, expect heat indices surpassing the 100s degrees Fahrenheit across coastal and urban areas, especially north of the Cordillera Central. During the nighttime, cool air advection over warm waters combined with land breeze convergence could result in another round of showers and possibly a few isolated thunderstorms across the Atlantic Coastal Waters. A similar weather pattern will persist on Friday too. The limiting factor for the conditions mentioned above is the lack of moisture which could reduce the frequency and coverage of this activity. Traces with African Dust Particles will also result in some haziness through the next few days.
Another tropical wave will move into the Caribbean Sea by late Friday or Saturday, increasing the intensity and frequency of showers across the islands.
Long TermSunday through Friday... The forecast for the upcoming workweek remains on track. A (TUTT) will continue to advance into the region. At the same time, an induced surface to mid level trough will move from the eastern Caribbean and move north of the islands, while a tropical wave crosses the southeastern Caribbean. The surface features will not move directly over the forecast area, but they will increase moisture, while the upper level feature will cause 500 mb temperatures to cool down. This increase in instability will increase the potential of showers and thunderstorms for Sunday and Monday. However, the position of the TUTT and the available moisture appears to favor further coverage and intensity of the activity on Monday.
The upper level trough lingers through Wednesday across the region, but late on Monday, a Saharan Air Layer will begin to filter in from the east, resulting in hazy skies, and also reducing the available moisture for shower production. By the end of the week, the global models shows a well defined tropical wave at 700 mb advancing over the area. However, with the dry air layer between 700 to 500 mb, shower activity should be limited in term of intensity and coverage, and with a seasonal behavior of morning showers over eastern Puerto Rico and the U.S. Virgin Islands, and afternoon convection along the western municipalities of Puerto Rico.
AVIATION... VFR Conditions will persist today. However, SHRA/TSRA will affect the interior and western PR between 07/16-22z, sometimes this activity could move in/around TJSJ/TJBQ/JPS. SHRA (rain showers) will also develop downwind from the USVI which could impact IST/ISX during the afternoon. Winds will be from the E-ESE at 10-15KT with higher gusts after 07/13Z with variations due to sea breeze. Winds will diminish overnight to around 10 KT or less.
Winds are expected to increase by tonight due to a surface high pressure centered over the eastern Atlantic. Seas will increase up to 6 feet with winds out of the east up to 20 knots. These choppy conditions are expected to continue through early next week.
.SJU WATCHES/WARNINGS/ADVISORIES... PR...High Rip Current Risk through Friday afternoon for North Central- Northwest.