Puerto Rico Weather

Area Forecast Discussion
National Weather Service San Juan PR
458 AM AST FRI JUN 10 2016

.SYNOPSIS...Mid level ridge will maintain a dry and stable air
mass aloft. This will result in limited shower activity across the
local islands through the end of the week. The next tropical wave
will move across the Eastern Caribbean on Monday...increasing
somewhat the shower and thunderstorm activity across the region.
Fair weather pattern will return to the islands on Tuesday as
Tropical Wave moves into the Central Caribbean.

&&

.DISCUSSION...Hot temperatures and hazy skies will prevail once
again today. Southeasterly flow will continue to push hot air into
the local area over the next few days. Ridge pattern will hold
through Sunday...maintaining the stable conditions across the
islands.

The next weather maker is expected early next week. A tropical
wave is forecast to move across the local region on Monday. This
will increase the potential for showers and thunderstorms over
Puerto Rico and the U.S. Virgin Islands. Breezy conditions are
likely from Monday to Wednesday. Another pulse of Saharan Dust
will reach the local islands on Tuesday...persisting through
Thursday/Friday. The onset of the Saharan Air Layer will also help
to limit the shower activity across the islands. Therefore... fair
weather pattern will prevail most of the next week.

&&

.AVIATION...Mostly VFR conditions expected across the local flying
area through the forecast period. Limited...if any shower activity
is expected as dry air with Saharan Dust particles remain over the
local area...which will cause haze. The visibility may be reduced to
below 10SM at times but it is still expected to be P6SM. SFC winds
from the E to ESE at 5-10kt early this morning... increasing to 10-
15kt after 10/13Z.

&&

.MARINE...Winds and seas are expected to diminish slightly during
the weekend. Winds will increase to 15-20 kt next week due to the
wave passage. Seas are forecast to remain below 5 feet through at
least midweek next week.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 92 79 92 78 / 10 10 10 20
STT 88 80 88 79 / 10 20 20 20

Area Forecast Discussion
National Weather Service San Juan PR
427 AM AST SUN JUN 12 2016

.SYNOPSIS...High pressure ridge aloft extends across the region
from the northwest Caribbean. Tutt low continues to linger and
extends across the Lesser Antilles from the Eastern Atlantic.
Surface high pressure ridge extends southwest across the East
Atlantic to just northeast of the forecast area..while a weakly
induced low level trough continues to shift westward across the
region. A tropical wave continues to cross the Lesser Antilles
and will move across the Eastern Caribbean later tonight through
Monday. An extensive area of suspended saharan dust and dry airmass
trails the tropical wave. This is expected to spread across the
region by Tuesday and linger during most of the upcoming week.

&&

.DISCUSSION...A few light showers were noted over the coastal waters
during the overnight and early morning hours. No precipitation was
observed observed over land areas as mostly dry and stable condtions
prevailed. mostly sunny skies can be expected during the morning...becoming
partly cloudy in the afternoon...diurnally and locally induced showers
develop mainly across parts of the interior and northwest sections
of Puerto Rico.

The tropical wave with axis just east of the Lesser Antilles will
enter and move across the eastern caribbean later tonight through
Monday. Satellite imagery showed convection associated with wave
being sheared northwards by tutt which extends across the Lesser
Antilles. However expect the tropical wave to eventually bring an
increase in low to mid level moisture across the region later tonight
and Monday. This will increase the chance for enhanced convection
across the coastal waters and portions of the islands by early
Monday morning and during the afternoon.

As previously mentioned...extensive area of saharan dust was noted
trailing this wave...so expect rapid drying and limited showers
and thunderstorm activity by Tuesday and during the remainder of
the work week. In addition...low level winds are to become more
southerly by Tuesday and the will also bring hotter and drier
conditions to the islands. Temperature are so far expected to
reach the low 90s in urban areas and lower elevations along northern
Puerto Rico and in the upper 80s across the U.S. Virgin Islands.

&&

.AVIATION...Mostly VFR conditions expected across most of the
local flying area until at least 12/16Z as dry air will prevail over
the region. SFC winds expected to be from the East at around 5-10
knots early this morning increasing to 10-15 knots after 12/13Z.
After 12/16Z SHRA/TSRA will redevelop over the western interior of
PR with mountain obscurations and MVFR/IFR conditions til 12/22Z.
For TNCM and TKPK...VFR will prevail until around 12/15Z. After
12/15Z clouds and SHRA from a tropical wave will approach the area
with some MVFR conditions.

&&

.MARINE...Seas 5 feet or less across the local waters with winds of
10 to 15 knots and occasional gusts. Winds and Seas may slightly increase
later tonight through Monday with the passage of the Tropical wave.
Please refer to the latest Coastal Waters Forecast issued by WFO
San Juan PR for additional info concerning the local Seas.

There is a Moderate risk of rip currents across portions of the
north facing coasts of PR.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 92 80 92 80 / 30 30 30 10
STT 89 81 88 81 / 30 30 30 20

Area Forecast Discussion
National Weather Service San Juan PR
420 AM AST TUE JUN 14 2016

.SYNOPSIS...An upper level ridge will remain as the main weather
feature promoting a fair and stable weather pattern across the
region until at least Thursday. By Friday...the ridge is expected
to be replaced by an upper level low. A surface high pressure
across the north eastern Atlantic will continue to induce a
moderate east southeast low level wind flow during the next
several days...resulting in warmer than normal temperatures and
hazy skies until at least Wednesday.

&&

.DISCUSSION...Doppler weather radar indicated only a couple of
isolated showers across the Caribbean waters overnight and early
in the morning. Elsewhere across the region...not precipitation
was detected as the region remains under the influence of an
upper level ridge. This feature will continue as the main weather
feature across the northeast Caribbean until at least Thursday.
However, the limited low level moisture will combine with the
strong daytime heating, sea breeze convergence and other local
effects to produce isolated to scattered showers and a couple of
thunderstorms each afternoon along the northern slopes of Puerto
Rico. The east southeast low level wind flow will continue to
promote warmer than normal temperatures especially along the
northern coastal municipalities of Puerto Rico. Hazy skies are
also expected as SAL continues to spread across the eastern
Caribbean.

&&

.AVIATION...VFR conds across all TAF sites and local flying area
thru the fcst prd. ISOLD SHRA FEW-SCT LYRS...FL020...FL050 til
14/14Z. Otherwise fair weather skies. Flight VIS >6SM but slight
HZ aloft aft 14/16Z due to suspended Saharan dust particulates.
Sfc wnd fm ESE overnight at 5-10 KT across USVI and
TNCM/TKPK...LGT/VRB ovr PR bcmg 10-15kts aft 14/14z with sea
breeze variations developing. VCSH psbl at TJBQ and TJMZ btw
14/18Z-14/22z. No sig operational impacts attm.

&&

.MARINE...Quiet marine conditions will remain across the regional
waters with seas of 2 to 4 and winds up to 15 knots. There is a low
risk of rip currents across most beaches of Puerto Rico...Vieques...
Culebra and the U.S. Virgin islands.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 93 80 91 80 / 10 10 20 20
STT 88 81 86 79 / 10 20 20 20

Area Forecast Discussion
National Weather Service San Juan PR
352 AM AST THU JUN 16 2016

.SYNOPSIS...Increasing moisture today and over the weekend will
generate better shower and thunderstorm activity with a threat of
urban and small stream flooding mainly in the interior western
portion of Puerto Rico.

At upper levels...A weak upper level low will drop south southwest
over the eastern tip of the Dominican Republic today and will
aid thunderstorm development over Puerto Rico. As the low drifts
slowly west northwest over the weekend and into next week, high
pressure will ridge over the area. A TUTT Low will deepen
northeast of the Windward Islands next week.

At mid levels...The focus of the high pressure stretched east to
west across the Atlantic Ocean north of the local area will shift
into the central Atlantic. Weak troughiness will move into the
eastern Caribbean mid week next week. Moisture north of the area
today moves southwest and fades. Better moisture associated with
a tropical wave moves past the area to the southwest.

At lower levels...High pressure over the Azores forms a ridge to
the north of the area and drives the current trade winds. It will
recede to the east. High pressure over Pennsylvania and New York
will move into the central Atlantic Saturday through Tuesday and
become the dominant feature that continues to drive the east
southeast trade winds over the local area through the end of next
week. A weak tropical wave will pass mainly south of the area
Friday night and Tuesday. A minor disturbance will also cross
through this Sunday before dawn.

&&

.DISCUSSION...Moisture is forming a band over the Leeward Islands
that was pulled in from the northeast from an old frontal
boundary. It will be the first moisture to cross the local area
tonight through Friday. Then moisture from weak tropical waves
will move into the area Sunday through Monday night. Although
drier Saharan air is crossing the tropical Atlantic at mid and
lower levels, it is mixing a little more deeply which is bringing
bands of better moisture there. Nevertheless mid layers remain
quite dry through the next 10 days and will limit the extent of
showers and thunderstorms that can form. Yesterday`s thunderstorms
did bring very heavy rain to a few local area in Maricao, Las
Marias and Utuado. Small hail also fell in Utuado due to the
intensity of the heating and convergence in the area. An inversion
also capped the activity early in the afternoon that caused the
storms to be stronger when they broke through. This cap is nearly
gone now.

Today precipitable water has spiked upward nearly an inch over
Bayamon to reach 2.5 inches and should cause much more extensive
showers even if they are a little weaker when they begin to block
the near-solstice heating. Such a high reading from the sounder is
unusual and we cannot be entirely confident of its accuracy until
the morning sounding is seen, so will be somewhat conservative
with POPs in all but western Puerto Rico today. Moisture and trade
wind flow is expected to continue through the weekend and into
Monday with showers, isolated thunderstorms and possible urban and
small stream flooding each day until then. Although moisture
moderates Tuesday and Wednesday it increases again toward the end
of next week with similar low-level flow. An upper level low will
also enhance shower and thunderstorm activity today through
Monday. A passing ridge will cause an ebb in the activity Tuesday
followed by northwest flow around the subsident side of a TUTT low
to the east northeast that consolidates early next week.

&&

.AVIATION...VFR conditions will prevail across all terminals during
the next 24 hours. HZ due to Saharan dust expected but with P6SM.
Low level winds expected to continue from the east at 10 to 15
knots. Sea breeze variations after 16/14z across northern PR
terminals...leading to development of shra/tsra across the western
interior...impacting mainly TJMZ btwn 16/18z-23z with MVFR conds
likely and mtn obscurations.


&&

.MARINE...Winds and seas remain relatively tranquil through
Saturday evening but winds at 850 mb will ramp up to almost 30
knots by early Monday morning. This will cause seas to increase
Sunday into Monday. Small Craft Advisory conditions are possible
on Monday...mainly in the Caribbean outer waters, but also in the
northeast portion of the Atlantic.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 90 79 90 79 / 10 10 30 40
STT 89 78 88 79 / 20 20 20 30

Area Forecast Discussion
National Weather Service San Juan PR
524 AM AST SAT JUN 18 2016

.SYNOPSIS...
At upper levels...a low aloft will continue over Dominican
Republic today, then it will moves northeastward to the Atlantic
Ocean. This low will become a trough Sunday into Monday. An upper
level ridge is expected to build from the Eastern Caribbean by
early next week. At the surface...a tropical wave, off to the east
of the Windward Islands, is forecast to enter the local region
late tonight or Sunday, followed by another one by late Monday
and into Tuesday.

&&

.DISCUSSION...
Clouds with embedded showers moved across the local waters
overnight, some moved inland across the windward sections, but
were brief and light. For the rest of this morning, expect mostly
sunny to partly cloudy skies with passing showers from time to
time across Eastern Puerto Rico and the U.S. Virgin Islands. The
instability created by the low aloft will combined with the
available moisture to produce another round of showers and
thunderstorms across the interior and western sections of Puerto
Rico during the afternoon hours. In addition, under the
prevailing southerly wind flow, some streamers are possible off
from El Yunque, to result in showers and thunderstorms across the
San Juan Metropolitan area, as well as off from the USVI.

Satellite imagery showed a tropical wave off to the East of the
Windward Islands, however is surrounded of Saharan Dust, which is
weakening this system. As this tropical wave enters the local
region on Sunday, moisture is forecast to increase and as it
interacts with the upper trof could lead to the enhancement of
shower and thunderstorm activity across the forecast area.
However, the amount of Saharan dust and dry air will be a limiting
factor to this activity. Another tropical wave is expected to
move across the local region late Monday or Tuesday.

&&

.AVIATION...VFR conditions will prevail across all terminals during
through arnd 18/17z. Some passing showers are expected VCNTY TKPK
TISX...TIST TJSJ during the morning hours. Periods of MVFR
conditions with and mtn obscurations from SHRA/TSRA expected over
TJMZ and TJBQ from 18/18z through 18/22z. Low level winds expected
to continue from the east-southeast at 10 to 15 knots up thru FL190.
Abv FL200 wind bcm SW up to 35 kt at FL400.

&&

.MARINE...
Latest coastal buoy observation indicated seas below 4 feet and
east winds up to 14 knots. An increase in seas and winds is
expected across the Caribbean waters through late Sunday and into
Tuesday.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 90 80 89 80 / 40 40 40 20
STT 90 80 88 79 / 20 40 40 30

Area Forecast Discussion
National Weather Service San Juan PR
528 AM AST MON JUN 20 2016

.SYNOPSIS...A tropical wave will continue to move across the area
through this afternoon. A drier airmass behind the wave will
encompass the local region late tonight into Tuesday.

&&

.DISCUSSION...Scattered to numerous showers were seen across the
Caribbean coastal waters overnight. This activity was associated
with a Tropical Wave...which is moving across the local area.
Better moisture of the wave will remain south of the local islands
the rest of the day. However...abundant moisture will combine with
daytime heating and local effect to produce showers and
thunderstorms this afternoon mainly over western interior Puerto
Rico.

After the passage of this wave...a drier airmass will encompass
the local region from the east. In addition...some Saharan air
particles are expected to affect the region later today and
tonight. For the rest of the work week...stable atmospheric
conditions are expected to prevail...as upper level ridge
dominates the region.


&&

.AVIATION...As tropical wave continues to exit the local area
Today...periods of MVFR conds are possible mainly across the
USVI/eastern PR terminals thru late in the morning hours...spreading
to the western terminals during the afternoon. Afternoon TSRA can
affect TJSJ. SHRA/TSRA is expected to continue thru the fcst period
across both Atlantic and Caribbean waters. E-ESE winds at 15-25 kts
will continue blo FL120.

&&

.MARINE...Due to the passage of the tropical wave...winds and seas
have increased. As a result...small craft should exercise caution
across most coastal waters due to winds up to 20 knots and seas up
to 6 feet.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 87 79 85 77 / 40 20 20 30
STT 88 80 82 79 / 60 20 20 30