Area Forecast Discussion
Issued by NWS San Juan, PR

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135
FXCA62 TJSJ 211113 CCA
AFDSJU

Area Forecast Discussion...CORRECTED
National Weather Service San Juan PR
713 AM AST Sun Jan 21 2018

.SYNOPSIS...Surface ridge and upper level ridge of high pressure
will create mostly fair weather conditions for Puerto Rico and the
U.S. Virgin Islands through Friday. Moderate to fresh trades winds
will cause isolated showers for most of the forecast area through
late next week. Friday, a trough of low pressure will move across
the Atlantic waters and possibly increase showers activity for
Puerto Rico and the U.S. Virgin Islands on Saturday.

&&

.SHORT TERM...Today through Tuesday...Partly cloudy skies prevailed
across Puerto Rico and the U.S. Virgin Islands overnight. Latest
satellite images depicted an area of low level moisture over the
U.S. Virgin Islands early this morning. This area of moisture will
spread across Puerto Rico this morning, bringing with it some
isolated passing showers. These showers will move quickly
westward. For this afternoon, some cloudiness with showers are
expected to develop across the western interior and west sections
of Puerto Rico.

High pressure system located north of the area will continue in
control of the weather locally. Trade winds will continue to
transport patches of low level moisture across the local islands
from time to time during the next couple of days.

&&

.LONG TERM...Wednesday through Monday...
Easterly trade winds will bring patches of low level moisture
periodically over the region through the long term period thus
scattered showers are possible during the morning and afternoon
hours. Strong brisk easterly winds can be expected through
Wednesday due to the strengthening surface high pressure system
to north of Puerto Rico. Otherwise, mostly fair weather conditions
across the forecast area until the end of next week when a trough
of low pressure moves into the Atlantic waters with some guidance
showing a frontal passage on Saturday.

&&

.AVIATION...VFR conditions are expected to prevail across all
terminals through at least 21/22z. Some light to moderate showers
can be expected in the vicinity of TIST, TISX and TJSJ throughout
the forecast period. Low level winds will continue mainly from the
east at 10 to 15 kts with higher gusts.

&&

.MARINE...Hazards weather conditions will prevail through Tuesday.
A long period northerly swell will cause seas to rise to 6 to 8
feet through Tuesday. Small craft advisories are in effect for
the Atlantic waters and passages as well across portions of the
offshore Caribbean waters. High rip current risk continues in
effect for the northern coast of the local islands, excluding St.
John with moderate risk. High surf advisory is in effect for the
Atlantic beaches of Puerto Rico.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  85  74  85  74 /  40  20  40  30
STT  78  77  79  78 /  20  30  40  20

&&

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

     High Surf Advisory until 6 PM AST this evening for Mayaguez and
     Vicinity-North Central-Northeast-Northwest-San Juan and
     Vicinity-Southeast-Western Interior.

     High Rip Current Risk through this afternoon for Vieques.

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

     High Rip Current Risk through this afternoon for St Croix.

AM...Small Craft Advisory until 8 PM AST this evening for Caribbean
     Waters of Puerto Rico from 10 NM to 17N-Coastal Waters OF
     Northwestern Puerto Rico out 10 NM-Coastal Waters of
     Northern USVI and Culebra out 10 NM.

     Small Craft Advisory until 2 AM AST Monday for Coastal Waters of
     Northern Puerto Rico out 10 NM.

     Small Craft Advisory until 2 PM AST Tuesday for Atlantic Waters
     of Puerto Rico and USVI from 10 NM to 19.5N.

     Small Craft Advisory until 2 PM AST Monday for Anegada Passage
     Southward to 17N.

     Small Craft Advisory until 8 AM AST Monday for Mona Passage
     Southward to 17N.

&&

$$

SHORT TERM...FC
LONG TERM....TW



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