Marine Weather and Tides
10/9/2019 Updated the Marine Zones.
9/4/2019 Fixed the weather maps due to NOAA moving them.
7/25/2019 New feature in the Airports section gives a link to 5 minute updates for data reports.
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|Sunrise 6:14AM||Sunset 6:02PM||Monday October 14, 2019 9:03 PM AST (01:03 UTC)||Moonrise 6:49PM||Moonset 6:46AM||Illumination 98%|
7 Day Forecast for Marine Location Near Esperanza, PRHourly EDIT Help
Area Discussion for - San Juan, PR  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxca62 tjsj 141747|
area forecast discussion
national weather service san juan pr
147 pm ast Mon oct 14 2019
An increase in showers and thunderstorms are expected over the
next several days as moisture increases from an approaching
tropical wave, and a tutt low cutoff from the main flow. Then by
the middle of the week unsettled and wet continues are expected
to prevail through the weekend. These conditions are a result of
increasing moisture from the deep tropics combining with a cutoff
low to the south of puerto rico. Also, this activity will be
propelled by local and diurnal effects.
Short term... Rest of today through Wednesday...
light easterly winds and increasing low level moisture convergence
will continue across the region today. The tutt and weak upper low
northeast of the northern leewards will remain in place, but is
expected to gradually become amplified and sink southwest across the
northern leewards and northeast caribbean by Wednesday while
strengthening. This will maintain a nw-n anticyclonic wind flow in
the upper levels through Wednesday and thus provide good ventilation
across the region through the period. Forecast soundings continue to
suggest increasing instability aloft resulting in better chance for
convection over the region during the period. This along with an
induced surface trough in place, and a tropical wave approaching the
area will favor a fairly moist and unstable environment at least
through Tuesday. This expected scenario will be followed a gradually
drying trend on Wednesday as a drier air mass accompanying a saharan
air layer will move across the region.
That said and given the current and expected weather pattern, the
forecast calls for mostly scattered showers across the local waters
during the rest of today with increasing potential for thunderstorm
activity throughout the day through Tuesday. Afternoon thunderstorm
activity over land should be focused across the interior and western
pr this afternoon, with enough periods of locally heavy rainfall to
cause urban and small stream flooding in isolated areas. Similar
conditions expected on Tuesday, however increasing cloud coverage
and rainfall intensity is forecast across the islands especially
during the afternoon hours.
On Wednesday, a drier airmass is forecast as an area of saharan dust
crosses the region trailing the tropical wave. Therefore expect
early morning and afternoon convection to be of lesser coverage.
Showers and isolated thunderstorm development will however remain
possible in isolated areas over and around the local islands.
Long term... Thursday through Wednesday...
the long-term period looks unsettled and wet as a result of deep
tropical moisture provided by several tropical waves, and a tutt low
that is forecast to cutoff south of puerto rico.
Thursday, a tutt low beings to deepen to the northeast of puerto
rico during the morning. Additionally, northerly winds will pull
moisture from the central atlantic into puerto rico Thursday
afternoon. The added moisture will combine diurnal and local effect
to produce showers and isolated thunderstorms. Late Thursday night a
tropical wave is forecast to move into the southern caribbean waters
just east of the u.S. Virgin islands.
Friday, the tropical wave will continue to transverse over the u.S.
Virgin islands, culebra and st.Thomas during the morning. Therefore
showers are expected during the morning across the aforementioned
areas. Also on Friday morning the tutt low is forecast to become
cutoff from main flow just to the southeast of puerto rico. The
position of the tutt low is the feature to watch closely if the
tutt low cutoff more to the southwest of the area this will
increase the upper-level divergence over puerto rico, would support
favorable upper-level conditions conducive for the development of
deep convection in the form of numerous showers and thunderstorms.
However, at this time guidance shows puerto rico remaining on the
substance side of the cutoff low, with available moisture and local
effects supporting the development of diurnal convection.
Saturday through the rest of the weekend guidance shows the cutoff
low weakening and moving to the northwest, or over puerto rico. Deep
tropical moisture is expected to continue to move over puerto rico
and the u.S. Virgin islands. Precipitable water values during this
time are forecast to range from 1.8 to 2.2 inches. The moisture and
local effects will support the development of showers and
thunderstorms during the afternoon mainly across the interior and
western areas of puerto rico. However, we can not rule out can't
showers and thunderstorms developing elsewhere during the afternoon.
On Sunday, another surge of moisture is forecast to push across the
u.S. Virgin islands and puerto rico this will continue the unsettled and
unsettled conditions across the region through Tuesday.
Tuesday, moisture is expected to decrease in the afternoon as a
drier air mass enters the area from the east, however, patches of
moisture are expected to move through the area with showers and
isolated thunderstorms as a result of diurnal and local effects.
Wednesday, a tropical wave is forecast to enter the caribbean waters
and increase moisture and showers and isolated thunderstorms.
PrevailingVFR durg prd. Shra isold tsra ovr ctrl and west interior
of pr and vcty usvi and northern leeward islands til 14 23z. Sct-bkn
lyrs nr fl022... Fl050 en route btw islands with isold shra tsra ovr
rest of flying area durg prd. Sfc winds fm e-se btw 10-15 kts with
sea breeze variations bcmg lgt vrb aft 14 23z. Shra isold tsra with
cause brief mtn top obscr ovr ctrl pr til 14 23z.
Choppy seas will continue this afternoon as a northerly swell
continues to weaken across the regional waters. Seas up to 5 feet
are expected over the next several days with the possibility of
showers and isolated thunderstorms. The high risk of rip currents
will continue to decrease as the northerly swell energy continues
to diminish across the local waters this afternoon.
Preliminary point temps pops
Sju 77 89 77 89 40 50 50 30
stt 79 88 77 88 50 50 50 20
Sju watches warnings advisories
Pr... High rip current risk until 6 pm ast this evening for north
central-northeast-northwest-san juan and vicinity-southeast.
Short term... Ram
long term... .Tw
Weather Reporting StationsEDIT (on/off)  Help NOTE: Click on distance to see the station location on a map
|Stations||Dist||Age||Wind||Air Temp||Water Temp||Waves||Pressure||DewPt|
|ESPP4 - 9752695 - Esperanza, PR||2 mi||63 min||NE 1.9 G 2.9||80°F||87°F||1014.9 hPa (+0.8)|
|41056||10 mi||63 min||ENE 7.8 G 9.7||84°F||86°F||3 ft||1013.6 hPa (+0.8)|
|CLBP4 - 9752235 - Culebra, PR||15 mi||63 min||83°F||88°F||1014.9 hPa (+1.0)|
|YABP4 - 9754228 - Yabucoa Harbor, PR||20 mi||63 min||82°F||76°F|
|CHAV3 - 9751639 - Charlotte Amalie, VI||32 mi||63 min||83°F||1014.8 hPa (+1.1)|
|41052 - South of St. John, Virgin Islands||38 mi||63 min||ENE 9.7 G 12||85°F||86°F||2 ft||1013.5 hPa (+1.0)|
|LAMV3||41 mi||63 min||82°F||87°F|
|41053 - San Juan, PR||42 mi||63 min||S 3.9 G 5.8||83°F||86°F||4 ft||1013.8 hPa (+0.8)|
|JOXP4 - Jobos Bay Reserve, Puerto Rico||42 mi||78 min||Calm||80°F||1016 hPa||73°F|
|SJNP4 - 9755371 - San Juan, PR||42 mi||63 min||S 4.1 G 5.1||82°F||87°F||1014.9 hPa (+0.9)|
|CHSV3 - 9751364 - Christiansted Harbor, Virgin Islands||48 mi||63 min||E 2.9 G 4.1||83°F||87°F||1014.5 hPa (+1.1)|
|LTBV3 - 9751401 - Lime Tree Bay, VI||48 mi||63 min||E 1.9 G 5.1||84°F||88°F||1014.8 hPa (+1.0)|
Wind History for Isabel Segunda, Vieques Island, PR(wind in knots) EDIT (on/off)  Help
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