High Surf Advisory 3, NWS JSJ

Area Forecast Discussion
National Weather Service San Juan PR
1212 PM AST Wed Feb 8 2023

...New UPDATE, AVIATION...

.UPDATE...
Issued at 1201 PM AST Wed Feb 8 2023

Sounding from San Juan at 08/12Z came in wetter today than the
last 24 hours with some moisture up to 30 kft despite intervening
dry layers. Winds with an easterly component also extended up to
25 kft allowing some convection to grow a little higher in a
slightly better environment (CAPE was 1557 J/Kg). Some showers
continue to develop upstream from PR and the U.S. Virgin Islands,
while the first signs of development are being seen in San German.
Forecast looks to be on track with minor adjustments.

&&

.SYNOPSIS...
Hazardous marine and coastal conditions will persist today and
will deteriorate even more tonight with the arrival of a second
pulse of a northerly swell. A variable weather pattern will
prevail for the rest of the workweek with frequent passing showers
and breezy conditions.

&&

.SHORT TERM...Today through Friday...

A surface high pressure centered north of the Bahamas will maintain
a strong trade wind flow out of the northeast. The low level
steering flow is expected to be around 20 knots today, and even
stronger on Thursday and Friday. The most recent satellite imagery
shows an area of enhanced moisture just north of the Virgin Islands.
Under a northeast flow, this feature will bring passing showers this
morning across the eastern municipalities of Puerto Rico and across
the U.S. Virgin Islands. Since the wind flow is strong, the showers
are expected to move fast without leaving high rainfall
accumulations, but wet roads and ponding of water on low-lying areas
can be anticipated this morning. Some showers may also develop over
southwestern Puerto Rico this afternoon, but the winds should move
them quickly across the Mona Channel.

On Thursday and Friday, the columnar moisture is expected to
decrease as a mid-level ridge promotes a drier air mass above 850
mb. However, induced patches of moisture will continue to reach the
islands irregularly, bringing additional showers for the same areas,
which is a typical pattern for this time of year. Once again,
significant flooding is not expected to occur with this activity,
but people across eastern Puerto Rico and over the USVI can
anticipate this on and off showery pattern to continue through
the end of the workweek.

&&

.LONG TERM...Saturday through Wednesday...

A variable weather pattern will persist for the long-period across
all the islands. At the surface, the pattern will be dominated by
the Atlantic high pressure generating breezy easterly winds. As
usual, the wind pattern will push patches of shallow tropical
moisture from time to time. According to the latest model
guidance, Saturday and Sunday appear to be the wettest days, with
PWat values up to 1.58 inches, according to the GFS global model.
Regardless of the PWat values, a mid-level ridge promoting a
trade wind cap could limit the lifetime of the showers. Unsettled
conditions could result, however,from the presence of a strong jet
and the "zonal flow" of a shortwave trough at the upper levels.
These upper level conditions will induce colder temperatures at
500 MB, decreasing to around minus 9 degrees. Given the expected
conditions, on Saturday into Sunday, expect frequent showers in
the morning over the U.S. Virgin Islands and eastern Puerto Rico,
then slightly stronger over the west in the afternoon. There is a
marginal risk for thunderstorms with the heaviest activity;
however, it will all depend on the amount of moisture moving
through the region.

From Monday onward, a frontal boundary moving out of the eastern
seaboard of the United States will induce a more southeasterly
wind flow over the region. Just like in previous days, patches of
moisture will reach the area at times, turning the skies cloudy
with passing showers. Additionally, the south component of the
wind will induce slightly warmer temperatures reaching the mid to
upper 80s in the coastal regions especially in northern Puerto
Rico.

&&

.AVIATION...
Mainly VFR conditions expected to prevail through the forecast area.
SHRA will continue across the local waters, and could reach the USVI
terminals and TJSJ at times. Additional SHRA are expected across the
Cordillera Central after 16Z, causing mountain obscurations.
Breezy conditions will persist, with winds out of the NE at 18-22
kts, with stronger gusts winds will subside, but will not die to
about 5-10 kts. Maximum winds WSW-W 40-50 kts btwn FL380-470.

&&

.MARINE...
Hazardous marine and coastal conditions will prevail for the next
several days, mainly due to the combination of fresh to locally
strong easterly winds and a northerly swell, maintaining seas up
to 7 feet today, with winds up to 20 knots. Elsewhere, seas will
remain up to 6 feet, where small craft should exercise caution.
Another pulse of a north swell will invade the local region later
tonight into tomorrow, building seas up to 10-12 feet.

Hazardous surf zone conditions will continue for the north and
east-oriented beaches of Puerto Rico and the northern USVI, where
a high risk of rip currents is in effect. For tomorrow, the second
pulse of the northerly swell will create hazardous and life-
threatening coastal conditions again, with large breaking waves
nearly 14 feet across the north coast. For more detailed
information, please refer to the Coastal Hazard Message product.

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...High Rip Current Risk through Friday afternoon for PRZ001-002-
     005-008-012.

     High Rip Current Risk from Thursday morning through Friday
     afternoon for PRZ010.

VI...High Rip Current Risk through Friday afternoon for VIZ001.

AM...Small Craft Advisory until 8 AM AST Sunday for AMZ710-741.

     Small Craft Advisory from 2 AM Thursday to 8 AM AST Sunday for
     AMZ712-715-722-732-742.

     Small Craft Advisory from 8 AM Thursday to 8 AM AST Sunday for
     AMZ725.

&&

SHORT TERM...WS
LONG TERM....RC
AVIATION...RVT

Perspectivas sobre las Condiciones Peligrosas del Tiempo
Servicio Nacional de Meteorologia en San Juan PR
401 AM AST miercoles 8 de febrero de 2023

AMZ710>745-PRZ001>013-090815-
San Juan y Vecindad-Noreste-Sureste-Este Interior-Norte Central-
Interior Central-Ponce y Vecindad-Noroeste-Oeste Interior-Mayaguez y
Vecindad-Suroeste-Culebra-Vieques-Las aguas cercanas y lejanas a la
costa del Atlantico y del Caribe-
401 AM AST miercoles 8 de febrero de 2023

Esta perspectiva sobre las condiciones peligrosas del tiempo es para
Puerto Rico.

.DIA UNO...Hoy y esta noche

.Lluvia Excesiva...Acumulacion de agua en carreteras y sectores de
pobre drenaje a traves del este. Inundaciones urbanas y de
riachuelos son posibles.

.Viento...Se esperan condiciones ventosas. Objetos que no sean
asegurados podran salir volando.

.Condiciones Maritimas...Oleaje de 7 pies o mas a traves de las
aguas del Atlantico y Pasaje de Mona. Condiciones maritimas
peligrosas para embarcaciones pequenas.

.Corrientes Marinas...Corrientes marinas amenazantes a la vida son
posibles en la zona de oleaje rompiente particularmente a traves de
las playas del norte de Puerto Rico y para Culebra.

.DIAS DOS A SIETE...jueves a martes

Se espera una marejada significativa del norte para el jueves al
sabado. Olas rompientes peligrosas haran que las playas del norte,
incluyendo Vieques y Culebra, se vuelvan muy peligrosas. Las
inundaciones costeras seran posibles el jueves y viernes. Riesgo
alto de corrientes marinas hasta el domingo. Condiciones ventosas
prevaleceran hasta el fin de semana. Aguaceros pasajeros se moveran
a traves de las islas, con acumulacion de agua en carreteras posible.

.Comunicado sobre informacion reportada por observadores...

Se exhorta la activacion de los observadores. Favor hacer llegar
cualquier informacion de inundaciones, vientos, oleaje y corrientes
marinas al Servicio Nacional de Meteorologia en San Juan.

AMZ715-725-VIZ001-002-090815-
San Tomas, San John e Islas Adyacentes-Santa Cruz-Las aguas cercanas
a la costa del Atlantico y las aguas costeras adyacentes del Caribe-
401 AM AST miercoles 8 de febrero de 2023

Esta perspectiva sobre las condiciones peligrosas del tiempo es para
las Islas Virgenes Estadounidenses.

.DIA UNO...Hoy y esta noche

.Viento...Se esperan condiciones ventosas. Objetos que
no sean asegurados podran salir volando.

.Condiciones Maritimas...Oleaje de 7 pies o mas a traves de las
aguas del Atlantico y Pasaje de Mona. Condiciones maritimas
peligrosas para embarcaciones pequenas.

.Corrientes Marinas...Corrientes marinas amenazantes a la vida son
posibles en la zona de oleaje rompiente particularmente a traves de
las playas del norte de San Tomas y San John.

.DIAS DOS A SIETE...jueves a martes

Se espera una marejada significativa del norte para el jueves al
sabado. Olas rompientes peligrosas haran que las playas del norte de
San Tomas y San John se vuelvan muy peligrosas. Las inundaciones
costeras seran posibles el jueves y viernes. Riesgo alto de
corrientes marinas hasta el domingo. Condiciones ventosas
prevaleceran hasta el fin de semana. Aguaceros pasajeros se moveran
a traves de las islas, con acumulacion de agua en carreteras posible.

.Comunicado sobre informacion reportada por observadores...

Se exhorta la activacion de los observadores. Favor hacer llegar
cualquier informacion de inundaciones, vientos, oleaje y corrientes
marinas al Servicio Nacional de Meteorologia en San Juan.