Special Weather Statement, NWS JSJ

Area Forecast Discussion
National Weather Service San Juan PR
1203 PM AST Mon Mar 1 2021

.UPDATE...

Windy easterly trades brought a surge of moisture across the
islands this morning, resulting in rainy conditions, cloudy skies
and gusty winds. Satellite imagery detected a dry air mass across
the Atlantic Ocean, which is forecast to move across the islands
later this afternoon. Therefore rain activity will slowly diminish
through the rest of the day. Winds continues from the NE at 15 to
20 mph with higher gusts. Maximum temperatures should remain in
the mid 80s along the coastal areas during the afternoon.

&&

.AVIATION...

VFR conditions will prevail today. Cloudy conditions will continue
across mainland PR through around 1/19z, except over JSJ, where
skies are turning mostly clear. However, easterly winds between 15
and 25 knots with gusts from 25 and 33 knots will affect the
local terminals. Winds will drop around 10 knots after 01/23z.
Should not rule out a few showers at times.

&&

.MARINE...

Seas and winds continue between 6 and 10 feet and out of the east
at 15 to 25 knots. Therefore, Small Craft Advisories are in
effect for the local waters until tomorrow morning.

Beachgoers, the risk of rip currents continues high for the north-
facing beaches of Puerto Rico, the southeast coast of PR, Culebra,
the northwestern beaches of St Thomas, and the north and east
coast of St Croix.

&&

.PREV DISCUSSION... /issued 501 AM AST Mon Mar 1 2021/

SYNOPSIS...Breezy conditions expected today. Surface and mid-
level high pressure systems will maintain drier conditions through
the end of the week. A trough will increase showers by the
upcoming weekend.

SHORT TERM...Today through Wednesday...
A surface high pressure located to the north of the region is
producing strong winds across the local waters and islands. This
system will generate an east-northeast wind flow at 15 to 20 mph,
with stronger gusts through late today and early tonight. Then, the
high pressure is expected to weaken, relaxing the pressure gradient
a bit, with a moderate steering flow continuing through the short-
term forecast period.

A drier air mass will continue to filter in, with precipitable water
values around 1.0 inch or less in the forecast for today and
tomorrow. This will act to inhibit any significant rainfall
development over the area. However, under a northeasterly wind flow,
advective showers may develop north of the area and move from time
to time over portions of northern and eastern Puerto Rico, as well
as across the U.S. Virgin Islands. By Wednesday, as the high
pressure migrates toward the eastern Atlantic Ocean, the wind flow
is expected to shift from the east-southeast. So far, the model
guidance are not suggesting any increase in moisture, but again,
some clouds carried by the trade winds may cause brief showers over
the islands.

LONG TERM...Thursday through Tuesday...

A mid-level ridge will dominate the local weather conditions
through the end of the workweek. This will promote stable
conditions aloft and maintain the trade wind cap across the
region. Precipitable water content through this period will be
around 1 inch, and diurnally induced afternoon showers should
result in minor rainfall accumulations. A surface high pressure
will continue to move further away into the central-eastern
Atlantic, while a polar trough and associated surface front exits
the U.S. East Coast by Friday. The base of the trough and the
front are expected at this time to remain just north of the
region, however, a pre-frontal trough is expected to develop in a
southeasterly wind flow and move over the region on Saturday.
Pooling of moisture is expected through the weekend into early
next week. Precipitable water content is forecast to increase from
1.75-2.00 inches during this time. Therefore, expect wetter
conditions and the potential for urban and small stream flooding
will increase due to periods of moderate to locally heavy
rainfall. Drier conditions are expected by Tuesday.

AVIATION...Mainly VFR conditions expected through the forecast
period. Strong winds will continue, out of the E at 15 to 20
knots. A patch of clouds may affect the USVI and Leeward terminals
early in the period, which could cause VCSH and brief periods of
MVFR conditions due to lower ceilings and reduced VIS.

MARINE...Choppy and hazardous seas are expected to continue
through at least Tuesday across the regional waters and Small
Craft Advisories are in effect for most of the local waters and
passages. Breezy conditions will continue today with winds from
the east to northeast at 20-25 kts with gusts up to 30 kts in
trade wind showers. There is a high risk of rip currents for most
of the beaches with northern and eastern exposure across all the
islands.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  84  71  85  72 /  40  40  30  30
STT  85  72  84  73 /  30  30  30  30

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...High Rip Current Risk through Tuesday afternoon for Culebra-
     North Central-Northeast-Northwest-San Juan and Vicinity.

     High Rip Current Risk until 6 PM AST this evening for Central
     Interior-Southeast.

VI...High Rip Current Risk through Tuesday afternoon for St Croix.

     High Rip Current Risk through late tonight for St.Thomas...St.
     John...and Adjacent Islands.

AM...Small Craft Advisory until 2 PM AST this afternoon for Coastal
     Waters of Southern Puerto Rico out 10 NM.

     Small Craft Advisory until 8 AM AST Tuesday for Caribbean Waters
     of Puerto Rico from 10 NM to 17N-Anegada Passage Southward
     to 17N-Atlantic Waters of Puerto Rico and USVI from 10 NM
     to 19.5N-Coastal Waters of Northern Puerto Rico out 10 NM-
     Coastal Waters of Northern USVI and Culebra out 10 NM-
     Coastal Waters of Northwestern Puerto Rico out 10 NM-
     Coastal Waters of Southern USVI Vieques and Eastern Puerto
     Rico out 10 NM-Mona Passage Southward to 17N.

&&

SHORT TERM...CAM
LONG TERM....FRG
PUBLIC DESK...LIS

Perspectivas sobre Condiciones Peligrosas del Tiempo
Servicio Nacional de Meteorologia en San Juan PR
410 AM AST lunes 1 de marzo de 2021

AMZ710>745-PRZ001>013-020815-
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 costeras
cercanas y lejanas a la costa del Atlantico y Caribe-
410 AM AST lunes 1 de marzo de 2021

Esta perspectiva sobre las condiciones peligrosas del tiempo es para
Puerto Rico y las aguas costeras del Atlantico.

.Dia Uno...Hoy y esta noche

.Viento...Se esperan vientos sostenidos en exceso a 20 mph (17 nudos)
para las aguas y sectores costeros.

.Oleaje...Se espera oleaje peligroso de hasta 10 pies hoy a traves de
las aguas y los pasajes.

.Corrientes Marinas...Existe un riesgo alto de corrientes marinas
para  la costa norte y sureste de Puerto Rico, asi como algunas
playas de Vieques y Culebra.

.Dias dos hasta el siete...martes a domingo

El riesgo de corrientes marinas continuara alto hasta tarde el
martes, luego se espera riesgo moderado hasta el fin de semana. Se
espera oleaje peligroso hasta el martes, con oleaje picado hasta el
jueves.

.Comunicado sobre informacion reportada por observadores...

No se espera activacion amplia de observadores. Favor de reportar
cualquier informacion sobre vientos, oleaje y corrientes marinas al
Servicio Nacional de Meteorologia en San Juan mientras siguen las
indicaciones de las autoridades locales y estatales.

AMZ715-725-VIZ001-002-020815-
San Tomas, San John e Islas Adyacentes-
Santa Cruz-Aguas cercanas del Atlantico y aguas
costeras adyacentes del Caribe-
410 AM AST lunes 1 de marzo de 2021

Esta perspectiva sobre las condiciones peligrosas del tiempo es para
Islas Virgenes Estadounidenses y las aguas costeras adyacentes.

.Dia Uno...Hoy y esta noche

.Viento...Se esperan vientos sostenidos en exceso a 20 mph (17 nudos)
para las aguas y sectores costeros.

.Oleaje...Se espera oleaje peligroso de hasta 10 pies hoy a traves de
las aguas y los pasajes.

.Corrientes Marinas...Existe un riesgo alto de corrientes marinas
para la costa noroeste de San Tomas y para la mitad norte y este de
Santa Cruz.

.Dias dos hasta el siete...martes a domingo

El riesgo de corrientes marinas continuara alto hasta el martes para
Santa Cruz, luego se espera riesgo moderado hasta el fin de semana.
Se espera oleaje peligroso hasta el martes, con oleaje picado hasta
el jueves.

.Comunicado sobre informacion reportada por observadores...

No se espera activacion amplia de observadores. Sin embargo, favor
de reportar cualquier informacion sobre vientos, oleaje y corrientes
marinas al Servicio Nacional de Meteorologia en San Juan mientras
siguen las indicaciones de las autoridades locales y estatales.