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Area forecast discussion 
National Weather Service San Juan PR
1039 PM AST Monday Jun 1 2015

Update...skies have cleared over the bulk of the area this
evening. However...additional middle-upper level clouds will move
into the area overnight. Infrared satellite also showed patches of low
level cloudiness approaching the Virgin Islands from the east.
The rest of tonight and overnight...expect tranquil weather
conditions across the islands with only a few passing showers
affecting the east portions of USVI and PR. No changes were
introduced to the forecast package this evening.

&&

Aviation...VFR conds expected through the forecast period. However...
afternoon rain showers/thunderstorms and rain over northwest PR may produce brief MVFR/IFR conds as
well as mountain obscurations between 17z-22z. East winds of 10-15
knots expected below 8k feet.

&&

Marine...seas of 2-4 feet with occasional 5 feet and winds around 15
knots can be expected through the end of the work week.

&&

Previous discussion... /issued 228 PM AST Monday Jun 1 2015/

Synopsis...deep layer moisture will continue over the Atlantic
waters through middle week as upper level trough north of the islands
moves into the central Atlantic. Middle to upper level ridge will
build over the Caribbean Sea for the next several days. Tropical
wave is expected to enter the eastern Caribbean by the end of the
work week.

Discussion...scattered to numerous showers with isolated
thunderstorms developed this afternoon over the western interior
and northwest sections of Puerto Rico. This activity was primarily
associated with the combination of deep low level moisture and
daytime heating. For the next few days...this same weather
pattern is expected...with some light passing showers affecting
mainly the eastern section of Puerto Rico and the U.S. Virgin
Islands during the morning hours with scattered to numerous
showers developing over the western interior and northwest
sections of Puerto Rico.

For the later part of the week...into the upcoming weekend...a
tropical wave currently located around 45 west this afternoon is
expected to arrive to the local area by Friday into
Saturday...increasing somewhat the chances for showers and
thunderstorms...with another pulse of moisture expected on Sunday
afternoon. After the passage of this wave...models suggest a dense
area of Saharan dust will approach the region by early next
week...which will limit the shower activity across the region.

Aviation...VFR across most of the local taf sites...except MVFR over
tjbq...tjmz due to after shra/tsra...and obscured mountains too. After 01/23z
few passing rain showers...across eastern PR...USVI...Leeward Islands taf
site are possible overnight...also brief MVFR are possible too.
Surface wind 10-20 knots with higher gust in/near shra/tsra...followed by
easterly winds at 5 to 10 kts overnight.

Marine...seas between 3 to 5 feet and winds up to 20 knots are
expected over the coastal waters. Small craft should exercise
caution.

&&

Preliminary point temps/pops...
sju 78 90 78 91 / 20 20 40 40
stt 79 87 79 87 / 30 30 40 40

&&

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

$$

12/11

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