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Area forecast discussion 
National Weather Service San Juan PR
256 PM AST Sat Aug 1 2015

Synopsis...broad upper level trough will form and hold through early
Monday across the central-eastern Caribbean. Meanwhile...middle level
trough will move over the islands on Sunday as tropical wave
enters the eastern Caribbean...bringing better low level moisture
by early Monday. However...dry and stable air returns late Monday/Tuesday
as middle level ridge establishes through midweek. Middle level
perturbations and wet trades will bring scattered showers from
midweek through the end of next week.


Discussion...mostly fair weather conditions with limited shower
activity prevailed today across the forecast area and similar
conditions are expected to continue through at least Sunday
night...with the exception of localized afternoon convection over
western PR. The combination of middle/upper level trough and a
tropical wave will bring better moisture over the islands by late
Sunday/early Monday. Early scattered showers over the USVI/eastern
PR and enhanced afternoon convection over western PR is expected
on Monday due the surge in moisture and favorable upper level
dynamics. Drying is expected quickly late Monday through
middle level ridge moves from the central to western Atlantic...but
from midweek forward...a series of middle level perturbations and
trade wind showers will pass from time to time across the forecast
area...increasing somewhat the frequency of early morning
showers/afternoon convection over western PR. However...rainfall
accumulations should stay below to near normal values for most of
the week.


Aviation...rain showers west PR until 01/22z. As a result...brief MVFR ceilings in
passing rain showers vcty tjmz. Few cumulus en Route by the way east PR and USVI with
passing rain showers. Surface wind from east at 15-20 knots west/higher gust up to 25
kts...becoming from east 5-10 kts after 22z.


Marine...near shore buoys are indicating seas of 3-5 feet across
the USVI and PR waters. Offshore Atlantic buoy running near 5
feet. East to northeast winds are around 15 knots with gusts in
the low 20s. Similar conditions are expected over the next few increase in winds is expected over the Caribbean waters
on Monday/Tuesday as tropical wave moves across the eastern
Caribbean Sea.


Preliminary point temps/pops...
sju 79 89 79 90 / 20 20 40 40
stt 78 89 80 89 / 20 20 50 50


Sju watches/warnings/advisories...



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