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Area forecast discussion 
National Weather Service San Juan PR
303 PM AST Wednesday Aug 27 2014

Synopsis...TUTT low will pass north of the area Thursday and
Friday with upper level ridge building in during the weekend.
Tropical wave is forecast to enter the eastern Caribbean Friday
afternoon and move across the northeastern Caribbean Saturday
through Sunday.


Discussion...mostly sunny to partly cloudy skies prevailed across
the local islands through the day...with isolated to locally
scattered showers observed across local waters and western Puerto
Rico. Temperatures were in the low 90s at lower elevations...with
easterly winds.

A typical weather pattern is expected to prevail across the local
islands through at least Friday...with passing showers across windward
areas in the morning followed by scattered showers and isolated
thunderstorms across the Cordillera Central and western Puerto
Rico in the afternoon. Although precipitable water will remain
near or just below average...afternoon convection might be enhance
as aforementioned upper level trough moves north of the area. As
winds shift to the northeast on Friday showers and T-storms will
be focused over Cabo Rojo and vicinity.

Increasing tropical moisture and better chance of showers and
thunderstorm activity is forecast for the upcoming weekend with
the approach of the next tropical wave. Uncertainty is high...
interaction between this feature and the TUTT to the north is
possible...intensity/organization of the convection will be
highly dependent on amplitude and timing. A fair weather pattern
is expected to prevail early next workweek as local islands
remains under upper level ridge pattern.


Aviation...VFR conds expected for almost all taf sites. Daytime
heating and local effects will aid in develop of isolated thunderstorms and rain over west PR
with thunderstorms and rain for tjmz and thunderstorms in the vicinity for tjbq until 27/22z along West/Mountain obcr over
Cordillera Central and western PR. Wind below fl200 from east-southeast 14-30
knots...strongest by the way fl100-fl150...gradually becoming from east during the afn.


Marine...a moderate to locally fresh easterly wind flow will prevail
through at least Thursday...becoming northeast Friday and Saturday.
A tropical wave is forecast to enter the eastern Caribbean Friday
afternoon and move across the northeastern Caribbean Saturday
through Sunday. This will bring an increase in shower and thunderstorm
activity across the regional waters. Small craft should exercise
caution due to winds up to 20 knots and seas up to 6 feet.


Preliminary point temps/pops...
sju 80 89 78 90 / 20 20 30 30
stt 81 90 80 89 / 30 30 30 30


Sju watches/warnings/advisories...
Coastal waters...none.



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