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Area forecast discussion...updated 
National Weather Service San Juan PR
1021 PM AST Tuesday Aug 19 2014

Synopsis...upper level ridge will build overnight through the end
of the week. Low pressure east of the Windward Islands expected to
enter the eastern Caribbean Sea late Thursday night and move into the central
Caribbean Sat.


Discussion...popcorn shower and T-storm activity will continue
overnight with middle-level drying expected Wednesday with areal covering of
showers diminishing. Moisture associated with next tropical wave
and low pressure will spread across the area Thursday with shower covering
increasing. Weather conditions likely to deteriorate rapidly beginning
Thursday night with winds and squalls increasing. Tropical cyclone
conditions possible during this time. Please refer to tropical weather
otlks from NHC. Significant heavy rainfall threat with this system.


Aviation...VFR conditions expected across all terminals through
the forecast period. However...vcsh will continue through the overnight
and early morning hours across most of the terminals. Between
20/16-21z...tsra/shra is expected over the western interior of
PR...affecting areas in and around tjmz and tjbq with brief MVFR
conds and mountain top obscurations. The 20/00z tjsj sounding indicated
east-NE winds at 6-26 kts from the surface to around 6 kft.


Marine...winds near 15kt through Thursday morning. Winds strengthening
Thursday afternoon with tropical cyclone conditions possible Thursday night
through Friday night. Raised winds 20-25 knots and seas 6-8 feet during
this period.


Preliminary point temps/pops...
sju 79 89 78 91 / 40 40 30 30
stt 78 89 79 91 / 40 40 30 30


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



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