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fxca62 tjsj 191000 
afdsju

Area forecast discussion
National Weather Service San Juan PR
600 am AST Thu Jan 19 2017

Synopsis...
a mid to upper level ridge is building over the region. At the
surface, a low pressure centered over the central Atlantic
continues to weaken a surface high pressure across the
southwestern Atlantic. As a result, winds are expected to continue
calm to light and variable. Mostly clear skies with pleasant and
cool temperatures were registered across the islands overnight.

&&

Discussion...
satellite imagery detected a dry air mass filtering across the
region overnight, this air mass limited cloudiness and shower
activity across the islands of Puerto Rico and the U.S. Virgin
Islands. Weather stations across the islands registered coastal
minimum temperatures between low and mid 60s and across the
mountains and valleys in the low 50s.

In general, fair weather conditions with mostly sunny skies and
no shower activity is expected today. As the surface low pressure
moves across the western Atlantic the pressure gradient is
forecast to relax. Winds are expected to diminish considerable
becoming calm to light and variable through the upcoming weekend.
By the weekend, a frontal boundary is expected to move close to
the local islands. As a result, pleasant minimum temperatures are
expected to continue during this period.

&&

Aviation...
mainly VFR conditions are expected to continue across all
terminals through the forecast period. Limited shower activity is
forecast across the local waters. Low level winds will continue
from the east-northeast at 10-15 kts with lighter land breezes after 19/00z.

&&

Marine...
marine conditions will continue to improve the rest of the week.
Mariners can expect seas between 2 and 5 feet across the coastal
waters and winds around 10 knots. For the beach goers, there is a
moderate risk of rip current across the local beaches.

&&

Preliminary point temps/pops...
sju 81 69 83 71 / 10 10 20 40
stt 80 70 79 71 / 10 20 20 20

&&

Sju watches/warnings/advisories...
PR...none.
Vi...none.
Am...none.

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