Marine Weather and Tides
10/6/2018 Colors of tide XTide graphs changed to emphasize that they were upgraded. See next note. Comments welcome.
10/4/2018 I have fixed XTide and updated the harmonic files. There were some name changes so you might have to click EDIT to find the new station name.
|Sunrise 6:26AM||Sunset 5:47PM||Monday November 12, 2018 9:03 PM AST (01:03 UTC)||Moonrise 10:40AM||Moonset 10:04PM||Illumination 24%|
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 122056|
area forecast discussion
national weather service san juan pr
456 pm ast Mon nov 12 2018
Synopsis The presence of abundant low level moisture with
favorable upper level dynamics will aid in the development of
showers and isolated thunderstorms across the forecast area
through the evening hours. Overnight and early morning showers
are expected to stream over the atlantic waters into coastal areas
of northern and eastern puerto rico and the u.S. Virgin islands.
This will be followed by afternoon convection over the local
islands on Tuesday. An approaching tropical wave will deteriorate
both weather and marine conditions starting late Tuesday night.
This weather pattern is expected to continue throughout the
Short term Tonight through Wednesday...
showers and isolated thunderstorms will continue to develop and
drift west-southwestward over portions of the interior and
southwestern puerto rico, as well as downwind from EL yunque and
the local islands. This activity is expected to dissipate at
around or before sunset. In addition, showers are forecast to
continue streaming over the atlantic waters and move over coastal
areas of puerto rico and the u.S. Virgin islands through the
overnight and early morning hours. The afternoon weather pattern
will be similar to today's weather pattern, influenced by local
and diurnal effects under a west southwestward wind flow.
The national hurricane center continues to monitor a tropical
wave located about 200 miles east of the leeward islands, that is
producing a large area of showers and thunderstorms. This
disturbance has now a 50 and 90 percent formation chance through
the next 48 hours and 5 days, respectively. So far, this system is
forecast to move westward to west-northwestward for the next
several days. However, unfavorable environmental conditions and
land interaction will inhibit tropical cyclone formation before it
reaches the local area. Regardless of the evolution of this
system, model guidance continues to depict a wetter weather
pattern across the forecast area by late Tuesday night into
Thursday. Significant rainfall accumulations, gusty wind
conditions and hazardous marine conditions are expected as the
main impacts from this system as it moves across the forecast
Long term Thursday through Monday... Issued 504 am ast Mon nov
the active aforementioned tropical wave located east of the
lesser antilles is still forecast to develop and move north of the
islands by Thursday based on the most recent guidance from the
national hurricane center. There is a slight toss up between both
gfs and ECMWF model guidance about how much this system develops,
but so far the GFS has initialized fairly well based on present
weather pattern and the location of this feature. Most recent
guidance from the national hurricane center this feature suggests
a 70 percent chance of development in the next 5 days. Regardless
of how much this active wave develops during the next few days,
expect a much wetter and unstable weather pattern for the forecast
areas through at least Thursday or early Friday, as the deep
layered trough pattern is to develop and linger across the region
through the end of the work week. This expected scenario will
provide favorable upper level support with good divergence aloft
and extensive pooling of moisture and low level convergence due to
a moist and dominant southeasterly wind flow, forecast to
continue through the end of the week.
By Saturday and through the early part of the following week, a
mid to upper level ridge is then forecast to build across the
region once again. This change in the overall pattern will aid in|
cutting off and suppressing widespread convective development. In
addition, the atlantic surface high pressure ridge is to build
north of the region and thus tighten the local pressure gradient.
This will lead to increasing easterly trade winds. By then,
periods of showers and thunderstorm activity if any, should be
limited to the overnight and early morning hours, followed by a
more typical limited afternoon convection each day. Somewhat
breezier conditions will also be possible during the latter part
of the period, therefore daytime afternoon shower activity may be
in the form of streamers and quick passing.
Aviation...VFR conds are prevailing across all terminal sites
with easterly winds of 10 to 15 kt with higher gusts up to 30 kts.
Shra iso tsra have started to develop over portions of eastern,
interior and western areas of puerto rico, and are affecting
terminals tjsj, tjmz and tjbq. This activity is expected to linger
until 12 23z. Sfc winds out of the east at 10 to 15 kts, then
winds turn to the north at 21 to 29 kft with winds ranging from 30
to 50 kts.
Marine... Marine conditions are forecast to deteriorate this
evening through the rest of the work week with seas forecast to
increase to up to 8 feet, occasionally up to 10 feet. First across
the local outer atlantic and caribbean waters, as well as the
local passages. Then, spreading into coastal waters and mona
passage including portions of the outer caribbean waters later in
the week. Precautionary statements and small craft advisories
will therefore be in effect for most of the local waters starting
this evening and through most of the work week.
Preliminary point temps pops
Sju 86 78 86 77 50 50 60 60
stt 88 78 88 78 50 50 60 60
Sju watches warnings advisories
Pr... High rip current risk through Tuesday afternoon for culebra-
High rip current risk through Tuesday afternoon for north
central-northwest-san juan and vicinity-western interior.
High rip current risk from Tuesday morning through Tuesday
afternoon for vieques.
Vi... High rip current risk through Tuesday afternoon for st croix-
st.Thomas... St. John... And adjacent islands.
Am... Small craft advisory from 8 pm this evening to 6 pm ast Tuesday
for caribbean waters of puerto rico from 10 nm to 17n.
Small craft advisory from 6 am Tuesday to 6 pm ast Wednesday for
coastal waters of northern puerto rico out 10 nm.
Small craft advisory from 8 pm this evening to 6 pm ast Saturday
for anegada passage southward to 17n-atlantic waters of
puerto rico and usvi from 10 nm to 19.5n.
Small craft advisory from 8 pm this evening to 6 am ast Thursday
for coastal waters of northern usvi and culebra out 10 nm-
coastal waters of southern usvi vieques and eastern puerto
rico out 10 nm.
Small craft advisory from 6 am Tuesday to 6 am ast Wednesday for
coastal waters of northwestern puerto rico out 10 nm-mona
passage southward to 17n.
Short term... Ds
long term... .Icp
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||33 min||NE 2.9 G 5.1||78°F||84°F||1014.1 hPa|
|41056||10 mi||33 min||NE 14 G 18||81°F||1013.5 hPa|
|CLBP4 - 9752235 - Culebra, PR||15 mi||33 min||81°F||84°F||1014.6 hPa|
|YABP4 - 9754228 - Yabucoa Harbor, PR||20 mi||33 min||76°F||72°F|
|CHAV3 - 9751639 - Charlotte Amalie, VI||32 mi||33 min||82°F||1014.3 hPa|
|41052 - South of St. John, Virgin Islands||38 mi||33 min||ENE 18 G 21||83°F||1012.6 hPa|
|LAMV3||41 mi||33 min||81°F||84°F|
|SJNP4 - 9755371 - San Juan, PR||42 mi||33 min||E 9.9 G 15||82°F||84°F||1014.8 hPa|
|JOXP4 - Jobos Bay Reserve, Puerto Rico||42 mi||78 min||E 1.9||1015 hPa|
|41053 - San Juan, PR||42 mi||33 min||E 16 G 18||83°F||1013.8 hPa|
|CHSV3 - 9751364 - Christiansted Harbor, Virgin Islands||48 mi||33 min||NE 6 G 11||82°F||83°F|
|LTBV3 - 9751401 - Lime Tree Bay, VI||48 mi||33 min||E 5.1 G 12||81°F||83°F||1014.8 hPa|
Wind History for Isabel Segunda, Vieques Island, PR(wind in knots) EDIT (on/off)  Help
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GOES Local Image of Puerto Rico EDIT
NOTE: East coast views moved to GEOS-16. They are experimental and not well supported by NOAA so they may not be correct so be warned. This change required redoing a large amount of the GOES code. If the image you are expecting is not showing, please let me know. You may need to use the EDIT function to update your location.
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