Small Craft Advisory 46, NWS JSJ

631 
WHCA72 TJSJ 181409
MWWSJU

URGENT - MARINE WEATHER MESSAGE
National Weather Service San Juan PR
1009 AM AST Mon Dec 18 2017

...Fresh to locally strong northeast trade winds will continue to
create rough and hazardous seas across most of the regional
waters...

AMZ722-725-181800-
/O.CON.TJSJ.SC.Y.0046.000000T0000Z-171218T1800Z/
Anegada Passage Southward to 17N-
Coastal Waters of Southern USVI Vieques and Eastern Puerto Rico
out 10 NM-
1009 AM AST Mon Dec 18 2017

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 2 PM AST THIS
AFTERNOON...

* WINDS... 15-20 knots with higher gusts possible.

* WAVES/SEAS...Rough seas up 7 feet with occasional seas up to 9 
  feet. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Small Craft Advisory means that wind speeds of 21 to 33 knots
are expected to produce hazardous wave conditions to small craft.
Inexperienced mariners...especially those operating smaller
vessels should avoid navigating in these conditions.

&&

$$

AMZ710-715-732-741-181800-
/O.CON.TJSJ.SC.Y.0045.000000T0000Z-171218T1800Z/
Atlantic Waters of Puerto Rico and USVI from 10 NM to 19.5N-
Coastal Waters of Northern USVI and Culebra out 10 NM-
Caribbean Waters of Puerto Rico from 10 NM to 17N-
Mona Passage Southward to 17N-
1009 AM AST Mon Dec 18 2017

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 2 PM AST THIS
AFTERNOON...

* WINDS...15-20 knots with higher gusts.

* WAVES/SEAS...Rough seas up to 7 feet with occasional seas up 
  to 9 feet. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Small Craft Advisory means that wind speeds of 21 to 33 knots
and seas of 7 feet or greater are expected to produce hazardous
wave conditions to small craft. Inexperienced mariners...
especially those operating smaller vessels should avoid
navigating in these conditions.

&&

$$

Area Forecast Discussion
National Weather Service San Juan PR
532 AM AST Mon Dec 18 2017

.SYNOPSIS...
Puerto Rico and the U.S. Virgin Islands weather will be controlled by
a mid to upper level ridge through Friday. On thursday a trough
of low pressure will move into the Atlantic waters and cause the
mid to upper level high pressure in the Atlantic to weaken. This
will cause unsettled weather across Puerto Rico and the U.S.
Virgin Islands through the Sunday.

&&

.Short Term...Today through Wednesday...
A surface high pressure over the western Atlantic will tight the
local pressure gradient inducing a northeast wind flow across the
islands. The breezy northeasterly wind flow will bring patches of
clouds and showers mainly across the U.S. Virgin Islands and the
northern and eastern portions of Puerto Rico at times. A ridge
pattern aloft will limit vertical development. The upper to mid
level ridge will slowly erodes after Wednesday as a TUTT low sink
from the northeast over the Northeastern Caribbean.

&&

.LONG TERM...Friday through Thursday...
The mid to upper level ridge that has brought somewhat fair
weather with an occasional isolated shower will weaken ahead of a
cold front that will move into the north Atlantic waters. The
front will push an upper level trough near the forecast area on
Friday. Friday will be a transition day from quiet weather to a
more unsettled pattern due to an increase in tropical moisture
across Puerto Rico and the U.S. Virgin Islands. The GFS and ECMWF
models are indicating that this active pattern will remain through
Christmas due to an tutt low that might cut off near Puerto Rico
and the U.S. Virgin Islands. At this time it's something to keep
an eye on over the next several days.

&&

.Aviation...
Trade wind showers will continue to affect TIST/TISX
TJSJ/TJBQ through 18/16z. As a result SCT-BKN cigs at FL025-FL060
are possible. All taf sites are expected to receive periods of -
SHRA/SHRA btwn 18/19-23z. Surface winds will continue at 10-15 kt
increasing at 15-20 kt with higher gusts aft 18/13z.

&&

.MARINE...
Northeasterly wind flow will continue over the next several days.
This will result in choppy and rough seas across most of the
local waters ways. Small craft advisories will remain in effect
until later this afternoon. Seas will be 5 to 7 feet with
occasional seas up to 8 feet with winds 10 to 15 kts with higher
gusts. High rip current risk remains for the northern facing
beaches while moderate to low risk for the other areas..

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  83  77  85  77 /  40  40  30  50
STT  86  79  86  76 /  50  30  30  50

&&

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

VI...Small Craft Advisory until 2 PM AST this afternoon for
     St.Thomas...St. John...and Adjacent Islands.

AM...Small Craft Advisory until 2 PM AST this afternoon for Atlantic
     Waters of Puerto Rico and USVI from 10 NM to 19.5N-
     Caribbean Waters of Puerto Rico from 10 NM to 17N-Coastal
     Waters of Northern USVI and Culebra out 10 NM-Mona Passage
     Southward to 17N.

&&

SHORT TERM...CAM
LONG TERM....TW

Perspectivas sobre Condiciones Peligrosas del Tiempo
Servicio Nacional de Meteorologia San Juan PR
456 AM AST lunes 18 de diciembre de 2017

AMZ710>745-PRZ001>013-190900-
San Juan y Vecindad-Noreste-Sureste-Este Interior-
Norte Central-Interior Central-Ponce y Vecindad-Noroeste-
Oeste Interior-Mayaguez y Vecindad-Suroeste-Culebra-Vieques-
Aguas cercanas y lejanas a la costa del Atlantico y Caribe-
456 AM AST lunes 18 de diciembre de 2017

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

.Dia Uno...Hoy y esta noche

.Inundaciones...Frequentes aguaceros pasajeros pudiera resultar en
acumulacion de agua en las carreteras y en areas de pobre drenaje.

.Vientos...Vientos sostenidos en exceso de 20 MPH se esperan a
traves de los sectores barlovento.

.Oleaje...Se espera oleaje picado/vigoroso de hasta 7 pies
que continue a traves de la mayoria de las aguas regionales hasta
esta tarde.

.Corrientes Marinas...Existe un riesgo alto de corrientes
marinas a traves de las playas orientadas hacia el norte de Puerto
Rico y Culebra.

.Dias Dos a Siete...martes a domingo

Condiciones ventosas se esperan hasta por lo menos mediados de
semana. Un patron mojado es posible despues de la semana laboral a
traves de la region. Ademas, un riesgo moderado a alto de corrientes
marinas tambien se espera para las playas del norte de las islas
locales durante los proximos dias.

.Comunicado sobre informacion reportada por observadores...

No se anticipa activacion amplia de observadores, sin embargo, se le
exhorta a los observadores que reporten Corrientes Marinas al
Servicio Nacional de Meteorologia en San Juan.

AMZ715-725-VIZ001-002-190900-
San Tomas, San John e Islas Adyacentes-
Santa Cruz-Aguas cercanas del Atlantico y aguas costeras adyacentes
del Caribe-
456 AM AST lunes 18 de diciembre de 2017

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

.Dia Uno...Hoy y esta noche

.Vientos...Vientos sostenidos en exceso de 20 MPH se esperan a
traves de los sectores barlovento.

.Oleaje...Se espera que oleaje picado/vigoroso de hasta 7 pies
continue a traves de la mayoria de las aguas regionales hasta esta
tarde.

.Corrientes marinas...Existe un riesgo moderado de corrientes
marinas a lo largo de las playas orientadas hacia el norte de las
Islas Virgenes.

.Dias Dos a Siete...martes a domingo

Condiciones ventosas se esperan hasta por lo menos mediados de
semana. Un patron mojado es posible alrededor de finales de la
semana laboral hacia la semana entrante. Ademas, un riesgo moderado
a alto de corrientes marinas tambien se espera para las playas del
norte de las islas locales durante los proximos dias.

.Comunicado sobre informacion reportada por observadores...

No se anticipa activacion amplia de observadores, sin embargo, se le
exhorta a los observadores que reporten Corrientes Marinas al
Servicio Nacional de Meteorologia en San Juan.