Areal Flood Advisory 13, NWS JSJ

Area Forecast Discussion...CORRECTED
National Weather Service San Juan PR
400 PM AST Mon Mar 20 2017

.SYNOPSIS....A wetter pattern is expected to prevail across the
local islands this week, particularly Friday and into the
upcoming weekend.

&&

.SHORT TERM...Tonight thru Thu Morning...

Moisture will continue to pool across the local islands through Tue
as an induced surface trough holds across the northeast Caribbean.
South southeast winds will prevail this afternoon and overnight
becoming more easterly Tue as this feature weakens. Under this
evolving pattern, the chance for showers and isolated thunderstorms
continues across the forecast area with passing showers expected
to prevail across the USVI and eastern Puerto Rico with locally
induced afternoon Tstorms over and north of the Cordillera and
Sierra de Luquillo.

.LONG TERM...Thu Night thru Day 8

Unstable condition are expected Thu night through early next week
as a sub-tropical jet remains north of the forecast area during
the entire period and close enough to destabilize the local atmosphere.
Moisture will also rise considerably late Thursday into early Friday.
Therefore, if the forecast holds, this will bring a considerable
amount of rain to the area late this week and early next week. It
is too early to determine if conditions are conducive for flash
flooding but localized urban and small stream flooding are
certainly possible with the forecast conditions.

&&

.AVIATION...VCSH will affect TJSJ, USVI and Leeward islands TAF sites
tonight. Latest TJSJ sounding indicated a very light and variable
wind flow from the SFC to around 13k feet, becoming westerly up to
70 knots aloft. SHRA will continue to develop over central mountain
range and western sections of Puerto Rico with periods of MVFR
conditions over TJMZ and possible over TJBQ until 20/22Z.

&&

.MARINE...Seas below 5 feet will continue to prevail across the
local waters through Tuesday. A northerly swell will reach the
area by Wednesday with seas up to 7 feet across the offshore
Atlantic waters. Another pulse of a larger northerly swells will
reach our local waters on Friday night.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  75  84  75  86 /  20  50  30  30
STT  72  84  74  84 /  60  60  40  40

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...None.
VI...None.
AM...Small Craft Advisory from 2 AM Wednesday to 2 AM AST Thursday
     for Atlantic Waters of Puerto Rico and USVI from 10 NM to
     19.5N.

&&

SHORT/LONG TERM...OM
AVIATION...JF