Caribbean - Central America Weather

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
457 AM AST Thu Jun 26 2025

.KEY MESSAGES...

*An area with slightly drier air and suspended Saharan dust
particles will promote hazy skies at least through Friday.
Another round is possible early next week.

*A trade wind perturbation will bring frequent passing and a
better chance for afternoon thunderstorms on Friday.

*Another tropical wave is expected to approach Puerto Rico and
the U.S. Virgin Islands from the eastern Caribbean by late
Saturday into Sunday.

*Winds and choppy seas will continue to promote life-threatening
rip currents.

&&

.SHORT TERM...Today through Saturday...

Weather conditions overnight remained mostly calm across Puerto Rico
and the U.S. Virgin Islands, with hazy skies and a light to moderate
easterly breeze between 8 to 20 mph, especially stronger near
coastal areas. Temperatures ranged from the upper 70s to low 80s in
urban areas and from the high 60s to low 70s in mountainous areas.
The presence of Saharan dust contributed to the hazy conditions and
typical summer temperatures.

Today, a relatively stable weather pattern is expected to persist
across the region as a mid-level ridge continues to dominate,
maintaining mostly dry conditions. Suspended Saharan dust will still
affect air quality and visibility. Therefore, citizens and visitors
are encouraged to follow the recommendations of the Health
Department. Temperatures are expected to remain in the upper 80s to
low 90s in urban and coastal areas and the upper 70s to low 80s at
higher elevations. Breezy conditions should prevail.

As the Saharan Air Layer shifts westward and exits the area by
Friday, a gradual increase in low-level moisture is expected, with
precipitable water values rising to between 1.40 and 1.70 inches. By
Friday into Saturday, the additional moisture combined with an
approaching upper-level trough will create a more unstable
atmosphere. These evolving conditions will increase the potential
for convective development, particularly during the afternoon hours.
Expect scattered to numerous showers and isolated thunderstorms,
especially across the interior and western portions of Puerto Rico,
as well as downwind from the U.S. Virgin Islands.

.LONG TERM...Sunday through Thursday...

A somewhat unstable and wet weather pattern is expected to unfold
across the region beginning this weekend. A retrograding mid- to
upper-level trough/low over the Mona Passage will continue to move
westward over the Bahamas. At the same time, a tropical wave
approaching from the east will bring a notable surge in tropical
moisture across the forecast area. This interaction will enhance
the potential for showers and thunderstorms, particularly Sunday
afternoon into the evening hours, with the greatest risk for
flooding rains concentrated during that period. Residents and
visitors should monitor for localized flooding, especially in
areas with poor drainage or near steep terrain.

Following this unsettled period, conditions are expected to
stabilize as a mid-level ridge builds and holds over the northeast
Caribbean by early next week. This feature will establish a trade
wind inversion, promoting subsidence and a drier atmosphere
aloft, which will significantly limit deep convective development
through midweek. Additionally, a Saharan Air Layer (SAL) is
forecast to arrive behind the tropical wave, resulting in hazy
skies, degraded air quality, and reduced visibility from Monday
through at least Tuesday. While a tropical wave will be moving
southward well away from the area, the local weather will remain
influenced by pockets of moisture embedded within easterly trade
winds, occasionally producing brief showers across windward
coastal regions, especially during nighttime and early morning
hours. Afternoon convection will remain localized, mainly
affecting western Puerto Rico due to diurnal, sea breeze and
topographic influences.

Temperatures are expected to trend above normal, especially under
the influence of the SAL, which will reduce overnight cooling and
result in warmer minimum and maximum temperatures across the
islands.

&&

.AVIATION...
(06Z TAFs)

VFR conditions across all TAF sites. Expect hazy skies with
visibilities around 6SM due to a SAL, which will limit rainfall
activity. Nonetheless, VCTS possible near TJBQ around 26/18z-23z.
Expect E winds ranging from 10-25 kt with occasional higher gusts
through at least 26/23Z.

&&

.MARINE...

The surface high pressure across the Atlantic will support moderate
to fresh easterly winds, resulting in choppy seas over local Atlantic
and Caribbean waters. The presence of suspended Saharan dust will
continue to result in reduce visibility through late tonight. A
trade wind perturbation will arrive around Friday, increasing the
potential for showers and thunderstorms, followed by another tropical
wave late Saturday night into Sunday.

&&

.BEACH FORECAST...

Wind-driven seas will maintain a moderate risk of rip currents
along most exposed beaches of the islands today and through much
of the forecast period.

&&

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
522 AM AST Sat Jun 28 2025

.KEY MESSAGES...

* A seasonal weather pattern will persist today, with a limited
excessive heat risk, especially in urban coastal locations.

* A tropical wave will approach Puerto Rico and the US Virgin
Islands from the eastern Caribbean later tonight into Sunday,
potentially promoting the formation of showers and thunderstorms
across Puerto Rico and the US Virgin Islands.

* An area with slightly drier air and suspended Saharan dust
particles will follow Sunday's tropical wave, creating hazy
skies and deteriorating air quality.

* Winds and choppy seas will continue to promote life-
threatening rip currents across exposed beaches.

&&

.SHORT TERM...Today through Monday...

Today through Monday...

Variable to locally showery conditions persisted over several
northern coastal areas as quick passing showers under east-northeast
steering flow affected those areas. Accumulations were generally low
since midnight, with only very localized areas reaching up to a
quarter to half an inch. Stronger shower activity remained over the
waters; isolated t-storm activity was seen over the Mona Passage
during the overnight hours. Lows ranged from the upper 70s to low
80s at lower elevations and from the 60s to low 70s at higher
elevations.

Winds are veering, with recent radar scans indicating showers now
being steered by more easterly flow, steering flow will continue
to veer to become east-southeasterly today. These will continue to
steer moisture into the islands today with precipitable water
(PWAT) values from 1.60 to 1.90 inches, locally up to 2.00 inches
over northwestern PR. Passing showers under breezy winds will
continue to start the day, while stronger afternoon convection
will concentrate over interior to west-northwest PR with lines of
showers possible downwind of El Yunque and the local islands.

An upper level low will remain well northwest of the local area,
as it continues to be displaced by a mid to upper level ridge that
will continue to dominate during the rest of the short term
period. A Saharan Air Layer (SAL) is also approaching the area,
with moderate concentrations reaching the islands by tomorrow
morning and persisting through the rest of the short term period.
This Saharan Dust can result in hazy skies and deteriorated air
quality. However, a wind surge and a tropical wave (with its axis
just east of 60W) will also reach the area by tomorrow, Sunday,
deteriorating weather conditions. This wave will also bring a
surge in tropical moisture, increasing PWAT values to above 2
inches over the islands, promoting more widespread showers over
the islands, especially during the afternoon over interior to W-NW
PR and downwind of the local islands and El Yunque.

An increased flooding risk will remain on Sunday. Drier air will
quickly move in late Sunday night and into Monday, maintaining
available moisture below 850mb. This plus the above mentioned mid
to upper level ridge and persisting SAL will promote a drier start
to the workweek. A limited variant of the diurnal pattern with
hazy skies and breezy to windy conditions will be present on
Monday. At to above normal temperatures will persist during the
period, with a limited to possibly elevated heat risk.

.LONG TERM...Tuesday through Saturday...

A seasonal weather pattern will influence the meteorological
conditions, featuring a mix of clouds and sunshine, as well as
clear skies from Tuesday to Thursday. On Tuesday, we can expect
lingering suspended dust particles due to a mid-level ridge.
Additionally, easterly trade wind disturbances, caused by a trough
located in the mid-to-upper levels off the northeast of the
Lesser Antilles, will introduce occasional increases in shallow
moisture across the region. These surges of moisture may lead to
brief showers, particularly in windward areas, followed by
afternoon convection in western locations. However, this activity
is expected to be limited in intensity due to the trade wind cap
and subsidence aloft associated with the persistent mid-level
ridge, which is anticipated to remain in place through at least
Wednesday.

Temperatures are expected to be above normal, particularly due to
the SAL, which will hinder overnight cooling and result in warmer
minimum and maximum temperatures throughout the islands during
the first half of next week.

Conditions are expected to change late Thursday into Friday due to
the approach of a retrograding mid- to upper-level trough/low and
a tropical wave. This situation may lead to increased shower and
thunderstorm activity in the US Virgin Islands and Puerto Rico.
Conditions should rapidly dry out after this wave by late Friday
night into next Saturday, promoting the typical advective pattern
overnight and in the morning, followed by afternoon convection.

&&

.AVIATION...
(06Z TAFS)

Mainly VFR conditions will persist. Quick moving SHRA/-SHRA over
mainly TJBQ, TJSJ & TIST (with VCSH over TISX & TJPS) will persists.
Winds bcmg E-SE during the day up to 15 to 20 kts with sea breeze
variations and local effects after 28/13Z, decreasing at 28/23Z.
However, brief MVFR conditions are possible near TJBQ after 28/17Z
due to possible VCTS, lines of showers could also reach TJSJ at this
time.

&&

.MARINE...

Mariners can expect choppy seas across the local Atlantic and
Caribbean waters due to the surface high pressure across the
Atlantic, supporting a moderate to fresh easterly wind flow. A
tropical wave is expected to arrive by late Saturday night into
Sunday, increasing the potential for showers and thunderstorms across
the region. Another pulse with suspended Saharan Dust Particles will
follow the tropical wave from late Sunday night through at least
Tuesday.

&&

.BEACH FORECAST...

Wind-driven waves due to breezy easterlies will promote a
moderate risk of rip currents at some exposed beaches of the
islands today and for much of the forecast period.

&&

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
512 AM AST Mon Jun 30 2025

.KEY MESSAGES...

* Moderate concentrations of Saharan Dust will continue to filter
in, leading to hazy skies and deteriorated air quality through
Monday, with lingering dust after. Another plume of Saharan Dust
can reach the region to end the week.

* Today, a limited heat risk will be present for urban and lower
elevation areas of the islands while the southern coastal plains
will have elevated fire weather conditions.

* Breezy winds will sustain choppy seas and maintain a moderate
risk of rip currents along exposed beaches over the next few
days.

* Another tropical wave is forecast to affect the islands on
Friday, again increasing shower and thunderstorm activity.

&&

.SHORT TERM...Today through Wednesday...

Since midnight, only minimal rainfall accumulations have been
detected across the islands. Minimum temperatures have ranged from
the upper 60s in the higher elevations of Puerto Rico to the upper
70s and warm low 80s at lower elevations across the islands. Current
satellite-derived precipitable water (PWAT) values indicate up to
around 1.4 inches over eastern Puerto Rico and the nearby islands,
gradually decreasing to about 1.30 inches over western Puerto Rico.

A mid-level ridge will build over the islands, promoting a dry air
layer between 850 and 700 mb. At the surface, high pressure over the
central Atlantic will maintain a tight pressure gradient across the
northern Caribbean, resulting in breezy wind conditions once again.
However, this pressure gradient is expected to gradually weaken by
midweek, leading to reduced breezy conditions through the rest of
the period. Saharan dust is embedded within the dry air layer,
contributing to hazy skies through at least Tuesday. The mid-level
ridge is also expected to hold through at least Tuesday, maintaining
a trade wind inversion around 850 mb. This will limit widespread
rainfall development, with only isolated afternoon convection
possible over western portions of Puerto Rico.

On Wednesday, the mid-level ridge will begin to erode as a mid-to-
upper-level low northeast of the forecast area deepens and
approaches the region. However, relative humidity in the 700-500 mb
layer will remain below normal for this time of year, which could
inhibit vertical mixing. At lower levels, patches of moisture
embedded within the trade winds will move over the area, causing
precipitable water values to fluctuate between 1.15 and 1.80 inches,
ranging from well below to above normal. As a result, an increase in
shower activity may occur on Wednesday due to marginal instability,
although it will be closely tied to the availability of moisture.
Mid-level dry air may limit deep convection overall, but isolated
development cannot be ruled out during the afternoon over western
Puerto Rico.

A limited heat threat will be present across urban and coastal
areas, particularly during the late morning and early afternoon
hours. This will be more noticeable when humidity levels increase,
resulting in higher heat indices. While not expected to reach
advisory criteria, residents in these areas should still take
precautions, especially during prolonged outdoor activity.

.LONG TERM...Thursday through Monday...

Although Thursday will start with below normal concentrations of
precipitable water (PWAT), peripheral moisture from an approaching
tropical wave will increase PWAT to around 1.8 inches by Thursday
afternoon and evening. A surface high over the Atlantic will
promote up to breezy east to east-southeast steering flow through
Saturday, backing thereafter. The diurnal shower pattern will be
limited for most of Thursday, with passing morning showers and
afternoon showers and stronger showers over western PR. Available
moisture will remain below 850 mb on Thursday. However, deeper
moisture will reach the area on Friday as PWAT values increase to
2 inches or more. Therefore, Friday is expected to be the wettest
day, as a tropical wave crosses the islands and a retrograding
mid- to upper-level low also approaches. This will promote a boost
in the diurnal pattern and overall increased shower and t-storm
activity over the region, a limited to elevated flooding risk will
remain. Galvez-Davidson Index (GDI) values are forecasted to
reach +45 on Friday, meaning that thunderstorm and heavy rainfall
potential will remain. PWAT values will quickly drop to below
normal by Saturday before bouncing back to around 1.8 in by Sunday
through Monday as moisture remains of the wave are circled back
towards the islands by the surface high. The mid- to upper- level
low will continue to be near the islands during the weekend and
into early next week, promoting some instability. 925 mb
temperatures will be above normal with a limited to possibly
elevated heat risk each afternoon. The presence of saharan dust,
increasing as the period continues, can also serve to limit
nighttime cooling. This saharan dust can also serve as a limiting
factor for Friday's tropical wave.

&&

.AVIATION...
(06Z TAFS)

Mainly VFR conditions are expected across the terminals during the
next 24 hours. Saharan dust will continue filter into the region.
Low to moderate concentrations of Saharan dust will result in HZ
skies, with visibility occasionally reduced to 5-6 SM. Winds will be
more ESE at up to around 15-20 kts with higher gusts, shifting to
ENE aft 22Z up to around 8-12 kts.

&&

.MARINE...

Mariners can expect choppy seas across the local Atlantic and
Caribbean waters due persistent moderate to fresh easterly winds.
Small Craft Should Exercise Caution over most local waters. A mass
of drier air with suspended Saharan Dust Particles will continue to
filter into the area, maintaining hazy skies through Tuesday. A
tropical wave is forecast to move over the local waters on Friday,
increasing shower and thunderstorm chances.

&&

.BEACH FORECAST...

A moderate risk of rip currents (life-threatening rip currents
are possible in the surf zone) will be in effect for most
northern, southwestern and southeastern beaches of Puerto Rico,
as well as for beaches of Culebra, Vieques, southern St. John,
southern St. Thomas and all but western St. Croix. Although
other areas have a low risk of rip currents, keep in mind that
life-threatening rip currents often occur in the vicinity of
groins, jetties, reefs, and piers. The low risk of risk of rip
currents will spread tomorrow to St. Thomas and St. John. Up to a
moderate risk of rip currents will remain for most of the period.

&&

.FIRE WEATHER...

Little to no rainfall is anticipated across the southern sections
of Puerto Rico. Dry air with Saharan Dust particulates is also
filtering into the region. Relative humidities can drop to near
44 to 50%. Wind speeds can reach around 16 to 21 mph with gusts
near 30 mph. KBDI values in Guanica and Cabo Rojo remains above
critical fire weather thresholds (661 and 628 respectively).
Therefore, weather conditions should be favorable for the spread
of wildfires along the Southern Coastal Plains of Puerto Rico.

&&

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
432 AM AST Tue Jul 1 2025

.KEY MESSAGES...

* Saharan dust will gradually decrease today, but high
concentrations of dust are again expected this weekend, just
after the passage of a weak tropical wave.

* Winds will be breezy, with choppy seas and a moderate rip
current risk anticipated.

* High heat indices, above 102 degrees are expected each day for
all the coastal and urban areas of Puerto Rico and the Virgin
Islands.

&&

.SHORT TERM...Today through Thursday...

Since midnight, the highest radar estimated rainfall accumulations
over land ranged from 0.10 to 0.20 inches, mainly over Isabela,
Aguadilla, Vieques, St. Thomas, St. John and eastern PR. Lows have
ranged from the upper 60s at higher elevations of Puerto Rico to the
upper 70s and low 80s at lower elevations across the islands.
Current satellite-derived precipitable water (PWAT) values indicate
up to around 1.3 to (locally) 1.5 inches over the area.

A mid-level ridge over the islands, continues to promote dry air
between 850 and 700 mb. At the surface, high pressure over the
central Atlantic will continue to promote breezy conditions. A weak
tropical wave will move well south of the islands today, over the
Caribbean Sea. Saharan dust concentrations will continue to
decrease, with lingering low amounts persisting through the period.
The mid-level ridge will hold through at least Tuesday, maintaining
a trade wind inversion around 850 mb. This will limit widespread
rainfall development, with only isolated afternoon convection
possible over W-SW Puerto Rico (under ENE steering flow) today and
over W-NW Puerto Rico (under ESE steering flow) tomorrow and
Thursday. A surge of moisture (a weak surface disturbance) will
arrive late tonight into tomorrow and then on Thursday peripheral
moisture from a nearby tropical wave will cause precipitable water
values to reach around 1.5 to 1.80 inches. However, patches of drier
air will also filter in. The diurnal pattern of passing
morning/overnight showers and afternoon showers and isolated
thunderstorms over W-NW PR, where a limited flooding risk will
remain, will continue. Tomorrow, the mid-level ridge will begin to
give way to a mid-to-upper-level low northeast of the area that will
deepen and approach the region. However, relative humidity in the
700-500 mb layer will remain below normal, possibly limiting
widespread convection. A limited heat threat will remain across
urban and coastal areas during the late morning to afternoon hours.

.LONG TERM...Friday through Tuesday...

A weak tropical wave will approach the islands on Friday. The bulk
of the wave will remain over the Caribbean Sea, but enough
moisture should trigger some showers over the Virgin Islands and
Puerto Rico, with stronger convection developing across western
Puerto Rico in the afternoon. Just like the last wave that moved
over the region, this one also comes with a lot of Saharan dust,
so skies will be hazy late on Friday and on Saturday. Later on the
weekend and early next week, a series of surface troughs will
also move into the region, but they will also be embedded in
Saharan dust. The pattern aloft will not favor deep convection,
but occasional showers will move into the islands at times, with
additional showers and isolated thunderstorms each afternoon
across the west. The winds will be driven by a surface high
pressure over the eastern Atlantic, at 10 to 16 kts. It will be
hot too, as it is expected for July, with heat indices above 102
degrees along all coastal and urban areas in the region.

&&

.AVIATION...
(06Z TAFS)

Mainly VFR conditions expected. Saharan dust will continue to
decrease today. ENE steering flow up to around 15 to 20 kts with
higher gusts will steer VCSH towards the terminals. Afternoon
convection forecast to concentrate west of TJPS'S VCTY. Winds
decreasing at around 01/22Z

&&

.MARINE...
Mariners can expect choppy seas across the local Atlantic and
Caribbean waters due persistent moderate to fresh easterly winds.
Small Craft Should Exercise Caution over most local waters. A weak
tropical wave is forecast to move over the local waters on Friday,
increasing shower and thunderstorm chances. Saharan dust will follow
the tropical wave, with hazy skies returning on Saturday.

&&

.BEACH...
Breezy conditions will maintain a moderate rip current risk for
most of the beaches of Puerto Rico and the Virgin islands.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
436 AM AST Wed Jul 2 2025

.KEY MESSAGES...

* Passing showers and gusty winds will continue today as small
patches of clouds continue to move into the region.

* A weak tropical wave is expected on Friday, followed by Saharan
dust this weekend, resulting in hazy skies.

* Seasonably hot temperatures are anticipated each day, with heat
indices above 100 degrees in the afternoon hours.

&&

.SHORT TERM...Today through Friday...

A trade wind perturbation promoted variable to showery weather
during the overnight hours. Steered by breezy ESE flow, these
showers left radar estimated accumulations over most of the islands
since midnight. The highest accumulations were north of Yabucoa's
urban areas with values ranging from 1.20 to locally near 2.00 in.
Lows have ranged from the 60s at higher elevations of Puerto Rico to
the mid 70s and low 80s at lower elevations across the islands.
Current satellite-derived precipitable water (PWAT) values indicate
up to around 1.6 to 1.8 inches over the area, as the perturbation
continues to bring a surge of moisture.

The mid-level ridge that affected us continues to move away to our
west, giving way to a mid-to-upper level low approaching from our
northeast. At the surface, high pressure over the central Atlantic
will continue to promote breezy ESE flow for most of the period.
Patches of moisture and showers with PWAT values of up to around 1.9
inches will continue to be steered towards windward sectors of the
islands today. Due to persistent showers during the overnight hours,
wet roads will be observed as the morning starts, especially at the
eastern region. Afternoon convection is forecast over W-NW Puerto
Rico today and during the period, with lines of showers also
developing downwind of El Yunque and the local islands. After drier
air moves through on Thursday, by late Thursday into early Friday,
peripheral moisture from a tropical wave will once again increase
PWAT values. The tropical wave itself will cross the area later on
Friday, increasing PWAT values to 1.8 to around 2 inches. However,
this wave appears weak and is surrounded by moderate to high amounts
of Saharan Dust, which can serve to further limit it and promote
hazy skies on Friday. Additionally, the bulk of the wave will remain
south of the islands. The increase in moisture should trigger
showers over the islands under the ESE flow, with stronger
convection developing across W-NW Puerto Rico, and downwind of the
islands and El Yunque, in the afternoon. A limited heat threat will
remain across urban and coastal areas during the late morning to
afternoon hours.

.LONG TERM...Saturday through Wednesday...

Surface high pressure over the central Atlantic will maintain
fresh trade winds across the region. At the lower levels, a dense
Saharan Air Layer will move into the islands, resulting in hazy
skies on Saturday and Sunday. Some leftover moisture will also be
available, so some passing showers will continue as well. For the
workweek, not many changes are anticipated, with a trade wind cap
inversion around 850 mb, and all the available moisture trapped
near the surface. A couple of weak tropical wave will move across
the region, but also some patches of light to moderate amounts of
Saharan dust as well. The weather pattern will be variable, with
passing showers over the Virgin Islands and eastern Puerto Rico,
and afternoon convection in western Puerto Rico. No significant or
widespread flooding is expected during the forecast period.
However, it will be hot, with the guidance forecasting heat
indices above 102 degrees for all coastal and urban areas of the
islands each afternoon.


&&

.AVIATION...
(06Z TAFS)

VFR conditions expected to prevail. SHRA will continue to move
through the region, moving at the VCTY of the terminals and over the
terminals themselves, at times. This can cause brief MVFR
conditions. ESE flow up to around 15 to 20 kts with higher gusts
will steer these SHRA and result in afternoon convection mainly over
TJBQ/TJSJ. Winds somewhat decreasing at around 02/22Z.

&&

.MARINE...
Choppy seas are expected to continue across the local Atlantic and
Caribbean waters due persistent moderate to fresh easterly winds.
A weak tropical wave is forecast to move over the local waters on
Friday, increasing shower and thunderstorm chances. Saharan dust will
follow the tropical wave, with hazy skies returning on Saturday and
Sunday.

&&

.BEACH FORECAST...
Moderate to fresh trade winds will maintain a moderate rip current
risk for north and eastern Puerto Rico and for the Virgin Islands
through the end of the week. A low risk is expected this weekend,
before the risk increases again to moderate by early next week.

&&

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
355 AM AST Thu Jul 3 2025

.KEY MESSAGES...

* Saharan dust will persist across the region through at least
Sunday.

* A Heat Advisory is in effect today from 10 AM to 4 PM for most
coastal areas of Puerto Rico. Heat index values between 108°F
and 111 F are expected. Residents should stay hydrated and
take frequent breaks when working outdoors.

* A moderate risk of rip currents is present along the northern
and eastern coasts of Puerto Rico and the U.S. Virgin Islands.

&&

.SHORT TERM...Today through Saturday...

Mostly tranquil conditions were observed across the islands through
the night hours. Some showers managed to move into eastern Puerto
Rico and the Virgin Islands, but rainfall accumulations were
minimal. Temperatures cooled down to the low and mid 60s in the
mountain, and into the 70s in coastal areas. The most recent
satellite derived precipitable water imagery shows an area of less
moisture approaching the Virgin Islands, so showers will gradually
taper off later this morning.

The winds will be driven by a surface high pressure over the central
Atlantic, coming out of the southeast at 10 to 15 kts, with stronger
gusts. These winds will make temperatures soar into the upper 80s
and low 90s, and with heat indices exceeding 108 degrees in some
urban and coastal areas, especially along northern and western
Puerto Rico. This level of heat affects most individual sensitive to
heat, especially those without effective cooling or adequate
hydration. Even if moisture is nearly average today, strong heating
should trigger showers and thunderstorms across the interior and
northwestern Puerto Rico, where isolated urban flood cannot be ruled
out.

Tomorrow, a weak tropical wave will approach the region. The
increase in moisture will once again trigger afternoon convection,
for the interior, west, and around the San Juan metropolitan area.
Other sections of the Virgin Islands, eastern and southern Puerto
Rico will receive some showers as well. After the wave departs,
Saharan dust will arrive, in moderate to high concentrations. This
will result in hazy skies, reduced visibilities and a deterioration
in air quality. Some low level moisture will be embedded in the
dust, so it will not be completely dry. Temperatures will continue
to be above normal in the next couple of days, so heat advisories
are likely each day.

.LONG TERM...Sunday through Thursday....

A relatively variable weather pattern is forecast across the
region from Sunday through Thursday, influenced by several upper-
level features, surface patterns, and an intrusion of Saharan dust
by the beginning of the period. On Sunday, there will be a slight
presence of instability aloft due to a cut-off low located over
Hispaniola that might result in moisture advection across the
area. Meanwhile, at the mid-levels (500–700 MB), a ridge will help
maintain a relatively stable environment aloft. At the same time,
a plume of Saharan dust is expected to move over the region, with
concentrations capable of reducing visibility between 0.20 and
0.30 inches, resulting in hazy skies and possible air quality
deterioration. Overall, Sunday appears to be a quiet day with hazy
skies and limited shower development. However, daytime heating
and the local mountains will lead to the development of afternoon
convection, particularly in the interior and western parts of
Puerto Rico. Similar activity will be possible for the U.S. Virgin
Islands in isolated areas, mostly in the evening hours.

By Monday, another cut-off low will migrate from the northeast
into the northern portion of the region, further increasing
moisture levels and cloudiness. This upper-level feature will
enhance patches of cloudiness and moisture, which will be
transported westward by the prevailing easterly trade winds. The
interaction between this feature, surface heating, and local
effects will result in scattered showers and isolated afternoon
thunderstorms, mainly over the interior and western sections of
Puerto Rico each day. Trade winds will persist from the east under
the influence of a broad surface high pressure system stall over
the central Atlantic. On Thursday, the pattern will remain
similar, with southeast winds gradually taking hold as a broad
surface high over the central Atlantic extends further into the
Caribbean. Days will remain variable, with occasional passing
showers in the trade wind flow during the morning and overnight
hours, followed by pockets of afternoon convection over interior
and western Puerto Rico. So far today, although model had some
high level of uncertainty, Wednesday into Thursday will be the
most unstable days for the long term period.

&&

.AVIATION...
(06Z TAFS)

Mostly VFR conditions expected to prevail through the forecast
period. Passing SHRA are expected across the Caribbean and Atlantic
waters, but with little impacts to operations. After 17Z, TSRA is
expected near TJBQ, with periods of reduced VIS and low ceilings.
Winds will be from the ESE at 8-17 kts, with stronger gusts.

&&

.MARINE...
A broad surface high pressure over the central Atlantic will
continue to result in moderate to fresh easterly winds across the
region. Therefore, wind-driven seas will result in choppy marine
conditions across the Atlantic waters and the Caribbean Waters.
Saharan dust particles will be in place, resulting in hazy skies
and limited shower activity until Friday, when another tropical
wave moves into the islands, bringing showers and thunderstorms.

&&

.BEACH FORECAST...
The wind-driven seas will continue to result in choppy marine
conditions across the coastal local waters. Therefore, there will
be a moderate risk of rip currents across northern and
northeastern PR. The risk will return to low by Friday.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
840 PM AST Mon Jun 12 2023

.UPDATE...Excessive heat remained the main hazard today, with heat
indices around 108-114 degrees across lower elevations of western
and northern Puerto Rico, where maximum daytime temperatures
peaked into the lower 90s. A preliminary rainfall totals analysis
indicated that showers affected an area extending from Yabucoa and
Humacao in southeastern Puerto Rico, westward across the interior,
to Aguada and Aguadilla in northwestern =Puerto Rico. Secondary
areas with measurable rains of up to a quarter of an inch fell
downwind from El Yunque into the San Juan metropolitan area and
downwind from the local islands into northeastern Puerto Rico and
neighboring islands. So far, the highest rainfall totals between
1-2 inches fell between Moca, Aguada, and Aguadilla. Nonetheless,
flooding impacts were not reported with today's activity. Winds
remained from the east at 10-20 mph with gusts up to around 30 mph
and sea breeze variations.

The moisture field's leading edge associated with a weak tropical
wave has moved over the U.S. Virgin Islands and will gradually
move over eastern Puerto Rico tonight into Wednesday. Shower
activity is expected to increase tonight over eastern Puerto Rico
and the U.S. Virgin Islands, followed by another round of showers
with possible isolated thunderstorms clustering over northwestern
Puerto Rico by Tuesday afternoon, where limited flooding impacts
are likely. Overnight minimum temperatures will range from around
65 degrees across higher elevations of Puerto Rico to about 80
degrees across windward areas and the local islands. Although the
general flow will remain out of the east at 10 to 20 mph, winds
will slowly become calm to light and variable tonight, influenced
by land breeze variations. Winds will become more east-
southeasterly at 10-20 mph, with gusts up to 30 mph by mid-
morning.


&&

.AVIATION...VFR to brief MVFR conditions expected during the next
24 hours. Expect SHRA to affect TJSJ, TJBQ, and the USVI
terminals throughout the period. Afternoon SHRA/TSRA likely near
TJBQ around 13/17-22Z. Calm to light and variable surface winds
gradually increasing to 10-20 mph from the east-southeast with
higher gusts and sea breeze variations around 13/14-22Z.


&&

.MARINE...The marine forecast is on track. Marine conditions
should remain favorable for small craft, with seas up to 5 feet.
Winds will stay easterly at 10-20 knots. As a result, small craft
operators should exercise caution due to wind-driven choppy seas.
A moderate rip current risk remains in place for most local
beaches.


&&

.PREV DISCUSSION... /issued 406 PM AST Mon Jun 12 2023/

SYNOPSIS...

An increase in moisture is expected from tomorrow into Thursday
as a tropical wave moves near the region. The heat threat will
persist for the rest of the workweek. Southerly winds will return
on Thursday into the upcoming weekend. Choppy seas will remain
across most of the offshore local waters. &&

SHORT TERM...Rest of Today through Wednesday...

Cloudy skies prevailed for most of the eastern third section of
Puerto Rico and the U.S. Virgin Islands during the morning hours.
The daytime temperature increased mid-morning, reaching 91 in the
SJU Luis Munoz Marin Airport. The rest of the area's experiment
values are from the upper 80he, the lower 90s, and mid-80s across
the mountains. Once again, heat indices rounded 105-110 degrees
Fahrenheit. Winds were more from the east-southeast, as suggest
the TJSU 12Z sounding.

For the rest of the day, expect mostly dry conditions with
localized showers across the interior sections. An increase in
surface moisture is expected starting tonight into tomorrow as a
moisture surge from the upcoming tropical wave reaches the local
islands. This increase in moisture in the early morning hours will
result in more frequent pesky showers. For tomorrow, the islands
can expect the bulk of the moisture associated with the proximity
of a tropical wave. Therefore, the forecast calls for more chances
of rainfall activity across the western interior sections of
Puerto Rico and the interior due to the easterly winds. Although
an increase in showers is expected, the activity will not be
widespread or impressive due to a broad mid-level ridge, resulting
in subsidence and drier air aloft.

The same water content and features will be present across the
area. Therefore the potential for afternoon convection is
forecasted as well for Wednesday. However, a slight change of the
surface winds is forecasted again as the high pressure moves
northward, creating a southeasterly wind flow across the area.
Therefore, the shower activity will focus on the island's
northwestern quadrant.

Daytime temperatures are forecast to remain in the upper 80s to
the lower 90s across the coastal areas and in the low to upper 80s
in the mountains. Heat indices should stay at the threshold for
limited for the eastern sections and elevate to significant across
the western half of PR tomorrow due to the easterly winds.
However, on Thursday, the islands can expect an increase in the
heat indices due to the southerly winds over the region again.

LONG TERM...Thursday through Tuesday...from previous
discussion...

Recent model guidance and the overall weather
pattern continued to suggest a series of weak short waves will
move just north of the region while eroding the upper level ridge,
which eventually breaks down and is replaced by an upper trough
during the latter part of the period. In the meantime expect
sufficient low level residual moisture to combine with daytime
heating and local effects to support afternoon convection over
parts of the east interior and west sections of Puerto Rico on
Thursday, By Friday and into the weekend another tropical wave is
forecast to approach the eastern Caribbean. This will bring
additional moisture and instability to the region again favoring
an increased chance for enhanced afternoon convection over parts
of the west section of Puerto Rico each afternoon and around the
U.S. Virgin islands, mainly during the overnight and early morning
hours. By then and into the weekend, winds are again forecast to
become more southeasterly, favoring the warmer and humid weather
conditions to return across Puerto Rico, Vieques, Culebra, and the
U.S. Virgin Islands. The maximum heat indices are expected to
again range between 108 and 111 degrees especially along the
northern sections of Puerto Rico and between 102 and 107 over
parts of the U.S. Virgin Islands, Culebra and Vieques. Low to
moderate concentrations of Saharan dust particulates will continue
to be embedded in the wind flow, causing hazy skies through most
of the period.

AVIATION...

SHRA will continue until 22Z for TJBQ. SHRA will increase in
coverage after 22Z across the Caribbean waters, mainly impacting
the USVI terminals. Brief periods of reduces VIS and low ceilings
are possible with this activity. Winds will be out of the ESE at
13 kts or less after 22Z, picking up after 13/14Z, at 15-22 kts,
and stronger gusts.

MARINE...

The marine forecast is still on track. A surface high pressure
over the central Atlantic will maintain an east-southeast moderate
to locally fresh wind pattern across the region. The surface winds
will induce choppy seas across most of the regional waters.
Therefore, small craft operators should exercise caution. In
general, seas should remain 6 feet or less tonight for the
offshore Atlantic waters and up to 5 feet elsewhere. There is a
low to moderate risk of rip currents for tonight. For tomorrow,
the risk across the north coast of Puerto Rico will increase to
moderate.

&&

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
441 AM AST Sat Jul 5 2025

.KEY MESSAGES...

* Saharan dust particles will remain across the region resulting
in hazy skies at least until Monday.

* Warmer conditions are forecasted for today with heat indices
that would rank between 100 to 111 Fahrenheit degrees from 10
AM to 2 PM. As a result a heat advisory is in effect for all
the coastal areas of Puerto Rico, including the vicinity of
Caguas.

* There is a low risk of rip current for all the coastal along
Puerto Rico, Culebra, Vieques and St. Thomas and a moderate
risk of rip current across St. Croix.

&&

.SHORT TERM...Today through Monday...

Fair weather was observed across the islands during the night hours.
Very brief showers were observed across the local waters, but
without impact to land areas. A surface high pressure will maintain
the wind flow from the southeast during the weekend, and out of the
east by Monday, at speeds of 14-19 kts, with stronger gusts. In the
flow, a dense Saharan Air Layer will persist, resulting in hazy
skies and reduced visibilities. A trade wind cap inversion will be
present at 850 mb too, with any little available moisture trapped in
the lowest level of the atmosphere. This moisture may result in a
couple of brief and weak showers across eastern Puerto Rico and the
Virgin Islands. Even if conditions are not favorable for strong
convection, an isolated, but strong, storm may develop in the
afternoon along the northwest due to strong diurnal heating.
Temperatures will remain above normal, with an elevated risk of heat
for Puerto Rico and a limited heat risk for the Virgin Islands
today. Everyone should stay hydrated, look for shaded areas and
avoid strenuous activities in the exterior.

Not many changes are expected for Sunday, but by Monday, the higher
concentration of Saharan dust will depart. A weak disturbance will
move into the region, bringing passing showers into the area, and
aiding in the development of showers and thunderstorms across the
interior and west. Although no widespread significant rain is
anticipated, some minor urban and small stream flooding could be
reported. Temperatures will be just a tad lower, but still with a
limited heat risk anticipated for Puerto Rico.

.LONG TERM...Wednesday trough Sunday...

A broad surface high pressure anchored across the central
Atlantic will dominate the weather pattern across Puerto Rico and
the U.S. Virgin Islands from Wednesday through Sunday. This
feature will promote southeasterly winds through Saturday,
gradually shifting to an easterly flow late Saturday into Sunday
as the high extends westward into the western Atlantic. At mid to
upper levels, a ridge pattern will establish over the region,
promoting increasingly stable conditions and suppressing vertical
cloud development. As a result, significant convection is not
expected during the period, with only brief and isolated showers
possible across eastern areas during the overnight and early
morning hours.

A surge of Saharan dust will affect the islands from late
Wednesday through Sunday, leading to hazy skies and further
reducing shower activity. The latest guidance from the NASA
Goddard Earth Observing System Model V5 suggests that the highest
concentration of Saharan dust is expected on Friday and Sunday,
with aerosol optical depth values ranging between 0.20 and 0.30.
This will result in the driest and haziest conditions during those
days, maintaining an overall pattern of warm, stable, and mostly
dry weather through the weekend.

&&

.AVIATION...

(06Z TAFS) VFR conditions expected to prevail through the forecast
period. HZ due to Saharan dust will persist, but VIS remaining at
P6SM. TSRA expected after 17z for TJBQ, with periods of reduced VIS
and low ceilings. Winds will be from the SE at 14-17 kts, and
stronger gusts.

&&

.MARINE...

A broad surface high pressure over the central Atlantic will
continue to result in moderate to fresh easterly winds across the
region. Therefore, wind-driven seas will result in choppy marine
conditions across the Atlantic waters and the Caribbean Waters for
the following days. Saharan dust particles will be in place at
least until Monday, resulting in hazy skies and limited shower
activity. Variable weather conditions will persist for the rest of
the weekend into the upcoming workweek.

&&

.BEACH FORECAST...

There is a low risk of rip current across all the coastal areas of
Puerto Rico including Culebra and Vieques and St. Thomas.
However, for St. Croix the risk will go up to moderate across the
exposed beaches. For the upcoming workweek the risk of rip
current will become moderate again across the northern coastal
areas of Puerto Rico and extending into the east and southeast on
Tuesday.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
500 AM AST Sun Jul 6 2025

.KEY MESSAGES...

* High-level clouds may slightly reduce daytime heating, but a
limited risk of excessive heat remains, especially affecting
sensitive groups.

* Fire danger is elevated today across southern Puerto Rico due to
very dry soils and fuels, low humidity, and breezy conditions,
increasing potential for rapid fire spread after ignition.

* Persistent Saharan dust will maintain hazy skies and reduced
visibility today, which may impact outdoor activities.

* Rip current risk is low today but will rise to moderate tonight
and in the coming days. Exercise caution, especially on exposed
beaches.


&&

.SHORT TERM...Today through Tuesday...

Mostly stable weather conditions prevailed during the night hours
across all the local islands. Late in the night and into the early
morning hours, a few isolated thunderstorms were detected by Doppler
radar over the Mona Passage. These thunderstorms remained over the
waters and did not affect land areas. Around 2 AM, some isolated
showers were observed across the eastern side. Shower activity was
relatively insignificant, and rainfall accumulations were minimal.
Overnight temperatures ranged in the 80s across the coastal areas
and the U.S. Virgin Islands, and in the lower 70s across most of the
mountain areas, with some locations reporting temperatures in the
upper 60s. Winds remained from the east at up to 10 mph, with land
breeze variations.

The forecast remains on track. Today, the islands will be under a
breezy pattern with easterly winds as a broad surface high-pressure
system remains in place across the central Atlantic, tightening the
pressure gradient. Under this pattern, Saharan dust particles will
persist across the region. According to the NASA Goddard Earth
Observing System Model V5, values of aerosol optical depth thickness
[550 nm] will stay between 0.20 and 0.30. This pattern will favor
mostly hazy skies with some cloudiness throughout the day.
Widespread shower activity is not expected; however, afternoon
convection is possible across the western interior due to local and
diurnal effects, with a limited flooding threat for the day.
Additionally, there will be a limited heat threat across the coastal
and urban areas with heat indices that could reach 105 to 108
degrees.

For the rest of the short-term period, stability will persist as a
mid-level ridge remains in place, providing drier air aloft and a
strong trade wind cap over the islands. Although stable weather
conditions will continue, trapped moisture at the 850 mb level will
favor some diurnal convection, mostly between 12 PM and 5 PM across
the western interior. For Tuesday, despite previous discussions
mentioning a tropical wave moving near the area, increasing the
potential for showers, global models now indicate that the bulk of
the moisture associated with this disturbance will remain well south
of the islands. Therefore, while some moisture is still expected,
widespread shower activity is not forecast at this time.

.LONG TERM...Wednesday through Sunday...

A trade wind perturbation will affect the region Wednesday,
bringing brief periods of enhanced moisture and localized showers.
Following this, a weak tropical wave will cross the area Thursday
into Friday, steered westward by a strong Bermuda-Azores High. A
wind surge will then bring breezy to windy conditions Friday into
the weekend, with 700 mb winds peaking near 35–40 knots. This
pattern will support enhanced low-level moisture transport, though
mid- to upper-level dryness and a strong trade wind cap inversion
will limit deeper moisture availability and convection. Dry air
above 850 mb will persist due to subsidence from mid-level ridging
and later reinforced by a Tropical Upper-Tropospheric Trough
(TUTT) expected to cross the region Saturday. The most significant
drying will occur into early Sunday, with precipitable water
(PWAT) falling well below climatological norms.

Limited phasing of moisture and instability will restrict
widespread or organized convection; however, some afternoon
convection remains likely each day following the general wind flow
and driven by diurnal heating and local effects. Activity may
increase late Sunday as the TUTT shifts west and PWAT returns to
typical levels. A moderate to high Saharan Air Layer (SAL) event
is anticipated from Thursday onward, coinciding with the drying
trend and strengthening winds. This will contribute to hazy skies,
reduced visibility, and overall atmospheric stability.

Winds will generally flow from east to east-southeast, shifting
briefly to east-northeast Saturday night into Sunday as the
surface high repositions over the western Atlantic. Temperatures
will remain near seasonal norms, with Friday likely the warmest
day due to the strongest southeasterly flow component. Except for
excessive rainfall hazards, all other weather hazards—including
periods of excessive heat, gusty winds, and isolated afternoon
lightning—are possible through the long-term period.


&&

.AVIATION...
(06Z TAF)

VFR conditions will persist along all the TAF sites during the
period. HZ and a diminution of VIS are still forecast until 07/23Z.
VCSH to SHRA is possible across TJBQ at around 07/19Z if a shower
develops along the western interior, diminishing the visibility
and lowering the ceilings. Winds will peak at 07/15Z from the E up
to 15 knots with gusty winds.


&&

.MARINE...

Moderate easterly winds will prevail today, but local effects will
lead to choppy seas near coastal areas, prompting small craft
operators to exercise caution. Moderate to locally fresh winds
will return tonight and persist over the next few days, expanding
the area where caution is advised. Saharan dust will keep skies
hazy through tonight, with another event expected later in the
workweek. Afternoon thunderstorms may affect coastal waters and
local passages, particularly near western Puerto Rico, each day.
In addition, tropical waves approaching Tuesday and Thursday will
likely increase the chances for showers, thunderstorms, gusty
winds, and locally higher seas.


&&

.BEACH FORECAST...

Moderate winds and improved marine conditions will result in a low
rip current risk across all beaches today. However, as winds
increase tonight and persist through the upcoming days, the rip
current risk is expected to gradually rise to moderate in select
areas—beginning along northwestern Puerto Rico tonight, then
extending to the north-central coast, Culebra, and Saint Croix on
Monday, and reaching Vieques and southeastern Puerto Rico by
Monday night. Beachgoers are advised to exercise caution,
particularly at exposed northern and eastern shorelines. For the
latest and most detailed updates on rip current risks, please
consult the Surf Zone Forecast (SRFSJU).


&&

.FIRE WEATHER...

The fire danger risk is elevated today as winds back from the east
and a drier air mass moves into the area. Persistent high-level
clouds may slightly reduce daytime heating, though they are
unlikely to significantly increase humidity or produce rainfall,
thus having minimal impact on lowering fire danger. Breezy
conditions combined with lower relative humidities, and very dry
and deteriorated soils and fuels—especially in the driest
southern plains and hills of Puerto Rico—will support an increased
potential for fire spread. Refer to the latest Fire Danger
Statement (RFDSJU) for additional guidance.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
500 AM AST Mon Jul 7 2025

.KEY MESSAGES...

* Normal to above-normal temperatures will persist, with a limited
heat risk daily across lower elevations and urban areas, posing
risks to vulnerable groups.

* Afternoon showers and isolated thunderstorms are likely daily,
driven by local effects and diurnal heating, even during drier
periods. Stay alert for lightning and sudden downpours.

* Breezy to locally windy conditions will cause choppy seas and a
modreate risk of rip currents over the next few days. These may
create hazardous conditions. Stay cautons and follow safety
advise.

* Moderate concentrations of Saharan dust are expected to return
later this week, resulting in hazy skies and reduced visibility,
which may minimize outdoor visibility and affect weather
observations.


&&

.SHORT TERM...Today through Wednesday...

A variable weather pattern prevailed during the night into the
early morning hours. Doppler radar detected some passing showers
over the Atlantic waters overnight. As the night progressed,
additional showers were steered across the region by northeasterly
winds, affecting northern and northeastern sections of Puerto
Rico. Around 2 AM, isolated to scattered showers were observed
across the metropolitan area, impacting municipalities such as
Carolina, San Juan, Canovanas, Catano, Bayamon, and Guaynabo.
These showers developed as a result of cold-air advection, which
enhanced shallow convective activity. Rainfall accumulations were
minimal. Winds were from the east-northeast at 10 mph or less.
Overnight temperatures ranged from the mid to upper 70s in coastal
areas to the upper 60s and low 70s across the mountains.

For this morning, a variable weather pattern will persist across
the islands as winds maintain a northeasterly component. By late
morning, winds are expected to shift to a more easterly direction
as the surface high pressure system extends into the western
Atlantic. As this transition occurs, trapped moisture with
precipitable water values between 1.40 and 1.60 inches will be
transported toward the islands by the prevailing flow. Under this
pattern, isolated to scattered showers are expected across coastal
areas and local waters in the morning, followed by increased
convective activity over western and interior Puerto Rico in the
afternoon due to local and diurnal effects. While the U.S. Virgin
Islands should experience mostly fair weather, brief trade wind
showers may develop, with localized ponding possible in areas
where showers briefly intensify.

From Tuesday into Wednesday, the upper-level ridge will shift
farther east of the Leeward Islands, leaving the islands under a
stable pattern. This feature will promote subsidence aloft, enhacing
drier air aloft and suppressing deep convection across the region.
However, at the surface, moisture content will increase as a
tropical wave and an easterly disturbance enhance convective
potential across the local forecast area. These combined dynamics
will support scattered showers and isolated thunderstorms across
eastern Puerto Rico and the surrounding waters beginning Tuesday
evening, with activity spreading into interior areas and the U.S.
Virgin Islands by early Wednesday. Accordingly, the forecast was
adjusted to reflect an increase in the probability of isolated to
scattered showers beginning around 16Z Tuesday over the offshore
northeastern Atlantic waters, progressing into northeastern Puerto
Rico, St. Thomas, and St. Croix by 20Z Tuesday. This will leave
early Wednesday under a variable weather pattern with increased
cloudiness and passing showers. Additionally, low concentrations
of Saharan dust will be present from Tuesday and continue into
Wednesday.

.LONG TERM...Thursday through Monday...

A weak tropical wave is expected to move through the region on
Thursday, steered by a strong Bermuda-Azores High, maintaining
near-normal moisture levels. A surface wind surge will arrive on
Friday, initially enhancing low-level moisture before a
significantly drier air mass settles in through the weekend. Mid-
to upper-level dry air and a trade wind cap inversion—reinforced
by a tropical upper-tropospheric trough (TUTT) to the
northeast—will limit deep convection during this period. More
favorable conditions are likely Sunday into early next week as the
TUTT shifts over Hispaniola and easterly trade wind disturbances
approach the area.

Lingering moisture will support isolated to scattered showers
early in the period, with significant drying expected from Friday
through Sunday, reducing rainfall potential. Even during the
driest periods, afternoon convective development—driven by diurnal
heating and local terrain effects—remains likely each day. Breezy
to windy conditions will prevail through the weekend, with
southeasterly winds supporting above-normal temperatures,
especially between Thursday and Saturday, when values are forecast
to exceed typical seasonal thresholds. Cooler air aloft may
arrive Friday and persist into Saturday; however, limited moisture
will likely prevent widespread convection. Rain chances are
expected to increase again from Sunday afternoon into Monday.

A Saharan Air Layer spreading over the region beginning Thursday
will contribute to hazy skies, reduced visibility, and continued
suppression of widespread convection through at least Saturday.
While excessive rainfall is not a concern until Sunday, other
weather hazards—including periods of excessive heat, gusty winds,
and isolated afternoon lightning—remain possible throughout the
long-term period.


&&

.AVIATION...
(06Z TAF)

VFR conditions will persist for the upcoming hours, with brief
MVFR cigs across TJSJ and TJBQ in the afternoon hours due to lower
ceilings and a reduction in VIS. Winds will continue from the
E-NE at 10 knots, backing to E at around 07/12Z, and increasing up
to 15 knots with gusty winds. VCTS are forecast at 07/18Z for
TJBQ.


&&

.MARINE...

Moderate to locally fresh winds will create choppy seas across
local waters over the next several days, prompting caution for
small craft operators. Afternoon thunderstorms may impact coastal
waters and local passages, particularly over western Puerto Rico
and the Mona Passage each day. Showers and thunderstorm chances
increase on Tuesday and Thursday with the passage of tropical
waves. Saharan dust is expected to return later in the workweek.


&&

.BEACH FORECAST...

With strengthening winds over the next several days, a moderate
rip current risk is expected to gradually expand across most local
beaches—from northwestern Puerto Rico, Culebra, and St. Croix
today, to all of northern Puerto Rico, parts of southeastern
Puerto Rico, and Vieques by tonight. Beachgoers are advised to
exercise caution, mainly along exposed northern and eastern
shorelines. For the latest detailed updates on rip current risks,
please refer to the Surf Zone Forecast (SRFSJU).

[cycloneye]

thunderstorms are expected each afternoon, especially in western and
interior sections.
Although the threat of excessive rainfall remains low until late
Sunday into Monday, other weather concerns.

&&

.AVIATION...
(06Z TAFS)

Mainly VFR conditions are expected to prevail across all terminals.
However, SHRA en route from the Leeward terminals may cause brief
periods of MVFR cigs and -RA. Then, diurnally induced afternoon TSRA
over northwestern PR should lead to tempo MVFR conds at TJBQ fm
07/17-21z. Elsewhere, mostly VCSH and brief -RA periods expected. HZ
will gradually increase during the next day or so, but VSBY should
remain P6SM. However, higher concentrations of Saharan dust return
from Thursday onward and visibilities could drop to 5-6 SM. Winds
will continue E-ESE at 14-19 kt with sea breeze variations and
higher gusts aft 08/14z.

&&

.MARINE...

Moderate to locally fresh winds will create choppy seas across local
waters over the next several days, small craft should exercise
caution. Small Craft Advisories will possibly be issued later on for
Wednesday. Afternoon thunderstorms may impact coastal waters and
local passages, particularly over western Puerto Rico and the Mona
Passage each day. Showers and thunderstorm chances increase on
through Thursday with the passage of tropical waves. Saharan dust is
expected to return later in the workweek.

&&

.BEACH FORECAST...

Increasing winds over the next several days will promote a
moderate risk of rip currents across the eastern, northern, and
southeastern beaches of Puerto Rico, Vieques, Culebra, St. Thomas. and
St. Croix. Life- threatening rip currents often occur in the
vicinity of groins, jetties, reefs, and piers.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
452 AM AST Wed Jul 9 2025

.KEY MESSAGES...

* Diurnally induced afternoon showers and isolated thunderstorms
are expected over portions of the Cordillera Central and western
PR each day. Passing showers will continue across the USVI and
eastern sections of PR during the night/early morning hours.

* Breezy conditions are expected through Wednesday. Choppy seas
and a moderate risk of rip currents will persist over the next
few days. These may create hazardous conditions across the
Atlantic waters.

* Moderate to high concentrations of Saharan dust are expected to
return by the second part of the workweek through at least
Sunday, resulting in hazy skies, reduced visibility, and poor
air quality.

&&

.SHORT TERM...Today through Friday...

Overnight, scattered to numerous showers moved across the local
waters, with some reaching windward areas of the U.S. Virgin Islands
and Puerto Rico. This activity was associated with a wind surge that
increased local winds and generated rough seas for mariners. Skies
were variably cloudy, with temperatures ranging from the low to mid-
60s in the mountains and valleys to the upper 70s and low 80s in
urban coastal areas.

A wind surge will bring scattered showers and stronger winds across
the region starting today. From Thursday to early Friday morning, a
tropical wave accompanied by a band of moisture with precipitable
water values ranging from 1.85 to 2.10 inches will move through the
area. However, higher concentrations of Saharan dust embedded within
the wave may limit overall shower development. As a result, a
similar weather pattern is expected each day, with passing showers
across the U.S. Virgin Islands and eastern Puerto Rico during the
night and early morning, followed by afternoon convection over
central and western Puerto Rico and streamer development downwind of
the USVI and El Yunque. Localized impacts may include ponding of
water on roads, poorly drained areas, as well as urban and small
stream flooding, particularly during heavier thunderstorms. Moisture
will rapidly erode after Friday morning.

Additionally, based on the latest model guidance, an area of
suspended Saharan dust particles is forecast to move across Puerto
Rico and the U.S. Virgin Islands as early as tonight, continuing
through the weekend. This will result in hazy skies, reduced
visibility, and deteriorated air quality across the region.
Sensitive groups should take precautionary measures, as airborne
particulates may impact respiratory health.

.LONG TERM...Saturday through Wednesday...

The latest model guidance continues to indicate the arrival of
Saharan Dust particles along with a notably dry airmass through at
least late Sunday. Additionally, mid to upper level dry air and a
reinforcing trade wind inversion will further inhibit vertical
cloud development, suppressing widespread convection. With this
setup, residents and visitors in Puerto Rico and the U.S. Virgin
Islands can expect hazy skies, reduced visibility, and potential
air quality concerns, particularly for individuals with
respiratory conditions. Breezy conditions will prevail through
Saturday, with persistent easterly winds supporting above-normal
temperatures, especially across coastal and urban areas.

By Sunday, a Tropical Upper-Tropospheric Trough (TUTT) is forecast
to shift westward toward Hispaniola and linger there through
midweek. Beginning Monday, the approach of easterly trade wind
perturbations will gradually enhance moisture levels across the
region. As atmospheric moisture increases, so will the potential
for shower and thunderstorm activity.

Tuesday currently appears to have the highest rainfall potential as
a tropical wave approaches the forecast area, bringing deeper
tropical moisture. However, the most intense part of the wave is
expected to pass south of Puerto Rico and the U.S. Virgin Islands.
Nevertheless, scattered showers and thunderstorms are anticipated
each afternoon, especially across interior and western areas. We
will continue to monitor conditions closely for any significant
changes.

&&

.AVIATION...
(06Z TAFS)

Mainly VFR conditions are expected to prevail across all terminals.
However, a wind surge will bring some passing SHRA/+SHRA, which may
cause occasional brief periods of MVFR cigs and SHRA over E-PR/USVI
terminals. Then, expect diurnally induced afternoon TSRA over the
interior and wester PR. Higher concentrations of Saharan dust return
from Thursday onward and visibilities could drop to 5-6 SM. Winds
will continue E-ENE at 15-20 kt with higher gusts and sea breeze
variations aft 09/13z.

&&

.MARINE...

A wind surge will promote rough seas due to moderate to locally fresh
winds across the local waters, accompanied by scattered to numerous
showers through at least Thursday morning. Another easterly
perturbation will reach the Lesser Antilles late tonight, moving near
the US Virgin Islands and Puerto Rico by late Thursday night and
early Friday morning. Another pulse of suspended Saharan dust
particles will arrive as early as late tonight and persist through
the weekend.

&&

.BEACH FORECAST...

Increasing winds over the next several days will promote a moderate
risk of rip currents across the eastern, northern, and southeastern
beaches of Puerto Rico, Vieques, Culebra, St. Thomas. and St. Croix.
Life-threatening rip currents often occur in the vicinity of groins,
jetties, reefs, and piers.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
410 AM AST Thu Jul 10 2025

.KEY MESSAGES...

* Showers will continue to move across the Atlantic and Caribbean
waters, as well as southern PR through the morning hours. Like
previous days, diurnally induced afternoon showers and isolated
thunderstorms are expected over portions of the Cordillera
Central and western PR today.

* Moderate to high concentrations of Saharan dust are expected to
return late tonight through at least Sunday, resulting in hazy
skies, reduced visibility, and poor air quality.

* Breezy to locally windy conditions will promote choppy seas and
a moderate risk of rip currents over the next few days.

&&

.SHORT TERM...Today through Saturday...

Moisture from a passing tropical wave generated scattered showers
and a few isolated thunderstorms across the region overnight. Driven
by a strong steering low, some showers moved over eastern, southern,
and northern Puerto Rico as well as St. Croix in the U.S. Virgin
Islands, with a few reaching further inland onto the central
interior since 8 PM AST. Radar-estimated rainfall accumulations
generally remained below a quarter of an inch across most areas,
expect in parts of southern Puerto Rico, particularly the coastal
areas of Guayama, where totals exceeded one inch. Surface observing
stations reported a persistent gentle to moderate breeze along the
coast and in some elevated windward areas, with sustained winds
around 10-15 mph and gusts up to 25 mph. Low temperatures remained
warm, in the low 80s across most of northeastern and southern Puerto
RIco, including the San Juan metro area, Culebra, and the U.,S.
Virgin Islands.

A tropical wave will continue moving away from the area today,
steered by a broad surface high over the western Atlantic. In its
wake, stronger east-southeasterly winds will bring breezy to windy
conditions and user in much drier air (with precipitable water
dropping to around 1.30 inches, well below typical levels), along
with moderate to high concentrations of Saharan dust. This marks the
start of a hazier, warmer, and more stable weather pattern across
Puerto Rico and the U.S. Virgin Islands, expected to persist
through the weekend. Meanwhile, a mid- to upper-level trough to the
northeast will gradually desplace a mid-level ridge and settle
northwest of the area by Saturday. However, its influence will
likely remain limited due to the dry and stable environment.

Today will be a transition day. Morning showers associated with the
departing tropical wave may linger, followed by isolated to
scattered afternoon showers and isolated thunderstorms over western
Puerto Rico driven by lingering moisture, diurnal heating and local
effects. Increasing dust and dry air will suppress most convection
later in the day, reducing visibility and affecting air quality,
conditions that may impact sensitive groups, while drier and fair
weather spreads across the U.S. Virgin Islands and eastern Puerto
Rico. Highs will reach the upper 80s to low 90s, with heat indices
elevated to levels warranting a Heat Advisory, mainly for lower
elevations and urban areas of Puerto Rico

From tonight through Saturday, expect persistently hazy, dry, and
warm conditions with minimal chances for rainfall. Winds will be
strongest Friday, reaching 25-30 knots before gradually easing to 10-
15 knots by Saturday. Friday is likely to be the haziest and hottest
day, with abundant sunshine and limited relief from the breeze.
However, warm conditions will potentially prompt the issuance of
Heat Advisories every day. Residents and visitors are advised to
take appropriate precautions during this period, especially those
sensitive to reduced air quality and heat.

.LONG TERM...Sunday through Thursday...

On Sunday, Saharan Dust concentrations will begin to diminish.
However, we still anticipate hazy skies across the U.S. Virgin
Islands and Puerto Rico. The latest model guidance continues to
indicate a Tropical Upper-Tropospheric Trough (TUTT) shifting
westward towards Hispanola and lingering there through the
beginning of the workweek weakening the high pressure system at
the surface and forcing the breezy to locally windy conditions to
diminish. On Monday and Tuesday, the approach of easterly trade
wind perturbations will gradually enhance moisture levels across
the region. As atmospheric moisture increases, so will the
potential for shower and thunderstorm activity, particularly
during the afternoon hours over western and southwestern Puerto
Rico, with pockets of showers over eastern Puerto Rico in the
morning hours. Additionally, model guidance indicate that moisture
will extend from the surface through the mid and upper levels of
the atmosphere, supporting increased atmospheric instability and
enhancing the potential for convective development during this
period. By midweek, a tropical wave is expected to approach the
forecast area, bringing increased tropical moisture. However, the
most intense part of the wave is expected to pass south of Puerto
Rico and the U.S. Virgin Islands. Nevertheless, scattered showers
and thunderstorms are anticipated each afternoon, especially
across interior and western areas. We will continue to monitor
conditions closely for any significant changes.

&&

.AVIATION...
(06Z TAF)

SHRA/TSRA will likely affect TJSJ, TJPS, and USVI terminals
through 10/13Z, with afternoon SHRA/TSRA expected near TJBQ
between 10/17-23Z, possibly causing brief MVFR conditions. VCSH
are also possible around TJSJ and USVI terminals throughout the
period, especially after 10/23Z. Moderate to high concentrations
of Saharan dust will generate hazy skies, with visibilities
reduced to 5-6 SM after 10/13Z. Breezy to locally windy winds of
16-22 knots between 10/13- 23Z, diminishing to 10-15 knots after
10/23Z.

&&

.MARINE...

An easterly perturbation will continue to reach the Lesser Antilles
and move near the US Virgin Islands and Puerto Rico by late today
and early Friday morning. Another pulse of suspended Saharan dust
particles will arrive as early as late tonight and persist through
the weekend.

&&

.BEACH FORECAST...

Breezy to locally windy conditions over the next several days
will promote a persistent moderate risk of rip currents across
most local beaches of Puerto Rico and the US Virgin Islands.
Beachgoers are encouraged to exercise caution as life-threatening
rip currents are possible in the surf zone.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
349 AM AST Fri Jul 11 2025

.KEY MESSAGES...

* High concentrations of Saharan dust will continue to promote
hazy skies, reduced visibilities and poor air quality through
the weekend, especially impacting sensitive groups.

* Hot temperatures will continue, with heat indices reaching
levels that affect most individuals sensitive to heat.

* A Heat Advisory is in effect today for all the coastal and urban
areas of Puerto Rico, including the Caguas Valley area.

* Breezy to locally windy conditions will promote choppy seas and
a moderate risk of rip currents across the region.

&&

.SHORT TERM...Today through Sunday...

Partly cloudy and hazy skies prevailed during the overnight hours
across Puerto Rico and the U.S. Virgin Islands. Light passing trade
wind showers moved briefly over land areas leaving minor rainfall
accumulations, mainly across the USVI and eastern PR. By midnight,
minimum temperatures were still in the low-80s across most coastal
and lower elevations of the islands. Meanwhile, across the higher
elevations of PR, temperatures were from the mid-60s to low-70s. The
wind was from the east to northeast between 6 and 12 mph with gusts
near 20 mph.

A Saharan air layer (SAL) with moderate to high concentrations of
Saharan dust will linger over the islands through the rest of the
short-term period. Therefore, expect hazy skies along with reduced
visibilities and poor air quality to persist through at least early
Sunday. A 700mb ridge moving north of the area from the tropical
Atlantic and a broad surface high pressure over the western Atlantic
will continue to promote breezy (15-20 mph) east to east-southeast
winds today. This surface high will weaken by this evening, while
another broad surface high builds from the central Atlantic during
the weekend. As the 700mb ridge shifts further into the southwestern
Atlantic, winds will acquire a northeasterly component from tonight
into the weekend. These changes in the wind direction will mainly
cause afternoon showers to develop each day further south than
previous days, and a slight improvement in heat indices,
particularly on Sunday.

For today and Saturday, a similar weather pattern is expected with
breezy and hazy conditions prevailing. Also, warmer minimum
temperatures at night due to the SAL preventing efficient cooling at
the surface will cause that days begin warmer than normal.
Therefore, hot temperatures are expected mainly across most coastal
and urban areas of Puerto Rico. Heat advisory conditions will likely
continue each day. Residents and visitors, are advised to take
appropriate precautions during this period, particularly those who
are sensitive to heat and poor air quality conditions.

.LONG TERM...Monday through Friday...

A enhancement in moisture levels is expected by the beginning of
the workweek with the arrival of several trade wind perturbations
into the islands. The latest precipitable water content shows
values between 1.60 to 2.00 inches from early Monday through late
Tuesday. Therefore, there is an increase in the potential for
shower activity across the area, in particular over eastern Puerto
Rico and the U.S. Virgin Islands during the morning hours.

As the week progresses, a tropical wave is expected to approach the
islands from the east by early evening on Wednesday and lasting
through at least Friday. The latest model guidances has the bulk of
the wave arriving into the area by Thursday morning, increasing the
chance for showers and thunderstorms across the region with PWAT
values up to 2.20 inches. Despite of the wave passage, moderate to
heavy showers and thunderstorms are anticipated each afternoon,
particularly across the central and western municipalities of Puerto
Rico. We will continue to monitor the weather conditions closely for
any significant changes in the forecast.

Saharan dust concentrations will begin to decrease on Monday.
Nonetheless, minor concetrations of these particles will continue to
linger across the region through Thursday. Another pulse of
Saharan dust will arrive by late Thursday/ early Friday following
the wave passage. This event will promote, once again, hazy skies,
reduced visibilities and deteriorated air quality throughout the
area until the weekend.

&&

.AVIATION...

(06Z TAFS)

Mainly VFR conditions are expected to prevail across all terminals
during the next 24 hours. However, VCSH cannot be ruled out across
all sites. Higher concentrations of Saharan dust are expected fm
11/14z-12/22z, this could lead to lower VSBY btw 5-6 SM. This may
cause false BKN/OVC cigs at times. Winds will continue E-ESE at 15-
20 kt with sea breeze variations and higher gusts aft 11/13z.

&&

.MARINE...

A surface high pressure across the central Atlantic will continue to
result in moderate southeasterly winds across the region. Therefore,
mariners can expect moderate to fresh easterly winds and choppy seas
across the islands through the weekend. An extensive Saharan Air
Layer will move across the Northeastern Caribbean lingering through
the weekend, and leaving hazy skies, reduced visibilities a
deteriorated air quality.

&&

.BEACH FORECAST...

A moderate rip current risk continues along the northern and
eastern facing beaches of Puerto Rico , Culebra, Vieques and St.
Croix. Always swim near lifeguards and obey posted warnings.
Conditions may be dangerous for inexperienced swimmers.

Expect hot and hazy conditions through the weekend, with
excessive heat posing a risk, especially in urban and coastal
areas. Heat indices may exceed 108°F, so stay hydrated, seek
shade, and avoid peak sun hours.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
438 AM AST Sat Jul 12 2025

.KEY MESSAGES...

* A lingering Saharan Air Layer (SAL) with moderate to high
concentrations will continue to promote hazy skies, reduced
visibilities and poor air quality across Puerto Rico and the
U.S. Virgin Islands through at least early Sunday morning.

* A Heat Advisory is in effect today for all the coastal and urban
areas of Puerto Rico, including the Caguas Valley area.

* A tropical wave will approach the islands by the middle of the
week, increasing moisture and the potential for showers and
thunderstorms.

&&

.SHORT TERM...Today through Monday...

Clear to partly cloudy and hazy skies prevailed during the early
morning hours across Puerto Rico and the U.S. Virgin Islands. Brief
passing showers were noted over land areas across eastern PR and the
USVI. However, no significant rainfall amounts were observed.
Minimum temperatures were from the upper-70s to low 80s across the
lower elevations to the mid-60s and upper 70s across the highest
elevations. The wind was light from the east to northeast.

A lingering Saharan Air Layer (SAL) with moderate to high
concentrations will continue to promote hazy skies and poor air
quality across the islands through at least early Sunday morning.
Hot temperatures are expected once again and a Heat Advisory will be
in effect from 10 AM to 5 PM today across the urban areas and lower
elevations of Puerto Rico. Residents and visitors, are advised to
take appropriate precautions during this period, particularly those
who are sensitive to heat and poor air quality conditions.

A TUTT-low north of the area today will gradually move west during
the rest of the period. This could enhance the diurnally induced
afternoon shower activity over western PR, with a slight increase in
the potential for isolated thunderstorm development. However, the
precipitable water content is expected to remain below normal levels
(~1.50 inches) until at least Sunday. On Monday, a trade wind
perturbation will move across the region, increasing shower activity
in general across the islands.

.LONG TERM...Tuesday through Saturday...

A trade wind perturbation is expected to arrive into the area on
Tuesday, increasing moisture into the area and the potential to
observe shower activity across the islands. The forecast have not
changed a lot with the previous model guidance, and continues to
suggest the arrival of a broad tropical wave by mid-week. The latest
precipitable water content analysis suggest values up to 2.10 inches
by Wednesday afternoon. Therefore, showers and thunderstorms are
likely over portions of central, western and eastern Puerto Rico,
and the U.S. Virgin Islands from Wednesday morning through the
evening hours. This fast moving wave is expected to exit the region
by late Wednesday, followed by a atmospheric perturbation on
Thursday.

By the end of the workweek, a drier air mass accompanied by another
pulse of Saharan Air layer is anticipated to arrive into the area by
Thursday, following the atmospheric perturbation passage over the
region. This event will limit the shower activity across the
islands and will promote hazy skies, reduced visibilities and
deteriorated air quality throughout the area until the weekend.

Hot temperatures will continue across the region next week. Maximum
temperatures are expected to remain in the upper 80s to low 90s
along the coastal and urban areas, and around the mid 80s in the
higher elevations. Heat indices could reach values above 105 degrees
Fahrenheit each day, particularly over the northern, western and
southern municipalities of Puerto Rico. Residents and visitors,
please be aware of these conditions and plan accordingly if planning
to do outdoor activities under sun exposure.

&&

.AVIATION...
(06Z TAFS)

Mainly VFR conditions are expected to prevail across all terminals
during the next 24 hours. However, VCSH cannot be ruled out across
all sites. HZ due to Saharan dust and reduced visibilities btw 6-8
miles expected. This may cause false BKN/OVC cigs at times across
the USVI terminals. Winds will increase from the E-ENE at 15-20 kt
with sea breeze variations and higher gusts aft 12/13z.

&&

.MARINE...

A surface high pressure across the central Atlantic will continue to
promote southeasterly winds across the region. Therefore, mariners
can expect moderate to fresh easterly winds and choppy seas across
the islands through the rest of the weekend. High Saharan dust
concentrations will continue to move across the northeastern
Caribbean through early next week, promoting hazy skies, reduced
visibilities and deteriorated air quality.

[cycloneye]

Area Forecast Discussion
National Weather Service San Juan PR
409 AM AST Sun Jul 13 2025

.KEY MESSAGES...

* Hazy conditions will continue over the region, but with minor
concentrations of Saharan dust.

* Afternoon showers and isolated thunderstorms are expected over
central and western Puerto Rico each day.

* A low risk of rip currents is expected today through Tuesday
morning. By Tuesday afternoon, increasing winds will result in a
moderate risk of rip currents along the north and east facing
beaches of the islands.

* A tropical wave will approach the islands by the middle of the
week, increasing moisture and the potential to observe showers
and thunderstorms.

&&

.SHORT TERM...Today through Tuesday...

Mostly clear skies prevailed across the islands during the early
morning hours. Scattered showers were noted mainly across the
regional waters, with a few moving over land areas along the north
and east coast of PR, and across the northern USVI. Minimum
temperatures were from the mid-70s to low-80s across the lower
elevations of the islands to the mid-60s and mid-70s across the
higher elevations of Puerto Rico. The wind was light with a
northeasterly component.

A TUTT-low north of the area will continue to move west as a ridge
builds over the northeastern Caribbean on Monday and Tuesday. At
lower levels, weak trade wind perturbations are expected to reach
the islands on both days. For today, hazy skies will continue over
the region, but with lesser concentrations of Saharan dust.
Meanwhile, upper-level cirrus clouds are expected to increase over
the islands under the influence of the TUTT. A weak surface high
pressure over the central Atlantic will promote light to moderate
trade winds, but a northeasterly wind component is present. This
pattern today should keep heat indices just a few degrees lower than
previous days, and a Heat Advisory will not be issued at this
moment. Afternoon showers with isolated thunderstorms enhanced by
the upper low are expected to develop mainly over portions of the
Cordillera and western PR.

For the start of the workweek, the trade wind perturbations are
expected to enhance the early morning showers between the USVI and
eastern PR, where ponding of water on roads and in poor drainage
areas is expected. Then in the afternoon hours, the combination of
the available moisture content with daytime heating and the sea
breeze convergence will trigger convection over and downwind of the
mountain ranges of PR. Localized urban and small stream flooding is
expected with this activity and mainly in western PR. East to
southeast trades will return promoting a warming trend once again,
particularly on Tuesday.

.LONG TERM...Wednesday through Sunday...

A wet weather pattern is expected for the first half of the long-
term forecast due to the approach of a broad tropical wave into the
region. This tropical wave is anticipated to reach the islands
between Wednesday and Thursday, promoting a high moisture
environment and unsettled weather conditions. The latest
precipitable water content guidance (PWAT) has values up to 2.10
inches, suggesting a very moist environment beginning by early
Wednesday and lasting through late Thursday. Therefore, showers and
thunderstorms are likely over portions of eastern, central and
western Puerto Rico, and the U.S. Virgin Islands during this period.
After the wave passage, a drier airmass will begin to filter into
the region. Nonetheless, pockets of moisture will continue to
filter from time to time, promoting isolated to scattered showers
over the islands. From Saturday onwards, a mid-level ridge is
expected to build near the region, promoting drier conditions and
stability aloft.

Recent model guidance continues to suggest the arrival of another
pulse of high concentrations of Saharan Air layer (SAL)into the
region. This event will also help to inhibit the development of
shower across the islands. Be prepared for hazy skies, reduced
visibilities and deteriorated air quality through at least the
upcoming weekend.

Hot temperatures will remain all week across the area with maximum
temperatures reaching upper 80s to low 90s along the coastal and
urban areas each day. Heat indices are expected to rise into values
above 105 degrees Fahrenheit each day as well, mainly due to the
combination of high temperatures and high moisture. Residents and
visitors, please be aware of these conditions and plan
accordingly if planning to do outdoor activities under sun
exposure.

&&

.AVIATION...
(06Z TAFS)

Mainly VFR conditions are expected to prevail across all terminals
during the next 24 hours. However, TSRA over the western interior of
PR may will cause mostly VCTS at TJPS/TJBQ, and brief MVFR cigs btw
13/18z-22z. HZ due to Saharan dust will gradually diminish today.
East winds expected btw 9-14 kt with sea breeze variations and
higher gusts aft 13/14z.

&&

.MARINE...

A surface high pressure across the central Atlantic will continue
to promote moderate easterly winds across the region. Moderate to
locally fresh easterly winds are expected to return by early next
week. Therefore, small craft operators will likely be encouraged to
exercise caution. A tropical wave will approach the region by the
middle of next week, increasing moisture and the potential to observe
showers and thunderstorms.

&&

.BEACH FORECAST...

There is a low risk of rip currents across all local beaches. However,
life-threatening rip currents may still occur, especially near
groins, jetties, reefs, and piers. Always swim near a lifeguard
and follow the advice of local beach patrols and flag warning
systems.

Starting by late Tuesday, a moderate risk of rip currents will
return to the north and east facing beaches of PR, Culebra,
Vieques and the U.S. Virgin Islands, accompanied by increasing
winds. Warm to hot conditions are expected to persist through the
week, with heat index values likely exceeding 100°F. Stay well
hydrated, seek shade frequently, and avoid outdoor activity during
peak sun hours.