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 6:02AM||Sunset 5:38PM||Thursday January 17, 2019 10:45 AM CST (16:45 UTC)||Moonrise 4:01PM||Moonset 1:25AM||Illumination 88%|
7 Day Forecast for Marine Location Near Pole Ojea, PRHourly EDIT Help
Area Discussion for - San Juan, PR  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxca62 tjsj 171518|
area forecast discussion
national weather service san juan pr
1118 am ast Thu jan 17 2019
Update A patch of low-level moisture, identified by satellite
and radar imagery by cloud clusters and showers, will continue to
affect portions of eastern puerto rico during the next few hours
as it continues to move west northwestward embedded in the trade
winds. So far, rainfall accumulation estimates have ranged
between one and two inches over isolated areas across northeastern
puerto rico. Cloudiness has gradually dissipated over land and if
this pattern continues, it will allow for locally and diurnally
induced showers to develop over the interior and western puerto
rico in the afternoon. Also, showers can be expected downwind from
the local islands and EL yunque area, but it would depend
directly on cloud cover. Following this feature, an area of drier
air will invade the area this evening, but another patch of level
moisture is forecast to approach the area tonight into early
Friday morning. This weather pattern will continue through at
least Saturday with patches of dry moist air moving over the area.
A drier weather pattern is expected on Sunday through next week
as the a mid to upper-level ridge amplifies overhead, eroding the
Aviation MostlyVFR conditions expected across all local
terminals through the forecast period. A patch of clouds and
showers moving over region will result in vcsh conditions across
tjsj, tjps, tncm and tkpk through at least 17 16z. Afternoon
convection could result in vcsh and bkn030-070 across tjsj, tjps,
tjmz and tjbq between 17 16z and 17 22z. Surface winds between
10-15 with sea breeze variations through 17 22z, becoming light
and variable overnight.
Marine Although a northerly swell will continue to spread
across the the atlantic waters and local passages, tranquil
marine conditions are expected to continue across the regional
waters today and tonight with seas up to 5 feet and east to
southeast winds up to 15 knots. There is a high rip current risk
for beaches along the san juan metropolitan area and north central
coast of puerto rico through late tonight. Elsewhere, a low to
moderate rip current risk is in effect.
Prev discussion issued 419 am ast Thu jan 17 2019
synopsis... Low-level moisture will continue to result in periods
of showers across the region through Saturday. A drier and more
stable weather pattern is expected starting Sunday and continuing
through the middle of next week as a mid to upper-level ridge
amplifies overhead. Winds are expected to increase from the
northeast by the middle portion of next week as a strong surface
high pressure moves across the western atlantic, tightening the
Short term... Today through Saturday...
occasional clusters of low to mid level moisture will continue to
make its way across the forecast area and bring periods of passing
showers to the coastal waters and the windward side of the islands
during the rest of the morning hours. A weak low level trough just
west and north of the region will maintain a light east to southeast
wind flow across the area through at least Friday, then become more
east to northeast by Saturday as a surface high pressure ridge will
builds north of the region across the west and southwest atlantic.
For the rest of today, expect cloud cover and shower activity to
diminish by late morning leaving partly sunny skies across the
forecast area. Locally and diurnally induced afternoon convection|
is however expected again during the afternoon mainly over parts of
the interior and west sections of puerto rico as well as around the
san juan metro. Some showers will be locally heavy especially in the
west to northwestern sections of the island. Model guidance and
present conditions now suggest that a mid to upper level trough will
linger across the region through Friday but will slowly lift east
northeast into the tropical atlantic. Therefore expect the shower
activity in the easterly trades to be further enhanced as they
are steered west northwest producing periods of locally heavy
rains. This in turn may lead to minor ponding of water on roadways
and in poor drainage areas. However, widespread convection is
still not expected during the entire period. This cool advective
pattern of early morning passing trade wind showers followed by
isolated to scattered afternoon convection will continue though a
least Friday. Conditions will gradually improve by Saturday as the
low level trough pulls away from the region and a high pressure
ridge builds both aloft as well as at the surface inducing an east
to northeast low level wind flow and a gradual strengthening of
the trade wind cap inversion.
Long term... Sunday through Thursday...
a drier and more stable weather pattern is expected by the second
half of the weekend through at least the middle of next week as
the aformentioned mid to upper-level ridge amplifies overhead,
eroding the low-level moisture. In fact, both the GFS and ecmwf
models indicate precipitable water values dropping below 1 inch at
times during the period, which would be close to 2 standard
deviations below normal for this time of the year. As a result,
mainly fair weather conditions can be expected across most of the
region with very limited shower activity. An increase in the winds
from the northeast is expected by the middle of next week as a
strong surface high pressure moves off the northeastern coast of
the united states into the western atlantic, tightening the
pressure gradient somewhat.
Aviation... PrevailingVFR at local terminals durg prd but vcsh at
tjsj tjnr tisx tist tncm tkpk. Bkn-ovc lyrs nr fl030... Fl060...
fl080... And shra en route btw pr and northern leeward islands til
17 14z. Shra and low cld lyrs may cause brief MVFR and mtn top obscr
ovr E pr as patches of moisture move across the region. Sfc winds
light and variable bcmg fm e-se 10-15 kts aft 17 14z with sea breeze
variations through 17 22z.
Marine... Tranquil marine conditions are expected to prevail
with seas ranging between 2 and 5 feet and east to southeast
winds up to 15 knots. A northerly swell is moving across the
atlantic waters and local passages and will continue through
Saturday. A high risk of rip currents is in effect for the beaches
located across north-central puerto rico and san juan and
vicinity through 6 am ast Friday.
Preliminary point temps pops
Sju 83 71 82 73 60 20 20 40
stt 83 72 83 72 40 40 30 40
Sju watches warnings advisories
Pr... High rip current risk through late tonight for north central-san
juan and vicinity.
Short term... Icp
long term... .99
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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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