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 5:24AM||Sunset 5:53PM||Tuesday April 23, 2019 5:50 PM CST (23:50 UTC)||Moonrise 8:43PM||Moonset 10:54AM||Illumination 80%|
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 232116|
area forecast discussion
national weather service san juan pr
516 pm ast Tue apr 23 2019
Synopsis An east to northeast wind flow will prevail through
Wednesday, becoming more easterly Thursday and Friday. Patches of
low-level moisture embedded within the low-level flow will result
in afternoon showers across interior and western portions of pr
each day. A wetter pattern is still anticipated by the second half
of the upcoming weekend into early next week as deeper moisture
and more favorable upper-level dynamics move across the area.
Short term Tonight through Thursday...
a drier than normal airmass has kept the region mostly dry,
although some showers have developed across interior portions of
pr during the mid to late afternoon hours. However, given the dry
air mass present, these showers have struggled to maintain
themselves as well as intensify. This drier than normal air mass
will continue to prevail through tonight, resulting in mostly
fair weather conditions across the local area.
For Wednesday, the low-level moisture content is expected to
increase slightly. Aloft, a mid to upper-level trough will
continue to be near the area with an 80 to 90 knot subtropical jet
at 250 mb overhead. Therefore, some divergence aloft will be
present. Showers are likely to develop mostly across interior and
southern portions of pr during the afternoon hours as the
available moisture combines with the diurnal heating and sea
breeze convergence. A few thunderstorms cannot be ruled out as
the temperatures in the mid-levels will be around -8 degrees
celsius and there will some divergence aloft as a result of the
jet. Given that the low-level steering flow is expected to be
very weak, less than 5 knots, the showers that do manage to
develop are expected to move very slowly. Therefore, rainfall
accumulations in excess of an inch are possible in some areas. The
rest of the region, including the u.S. Virgin islands, is
expected to observe mostly dry weather conditions.
Weather conditions are expected to become more stable aloft on
Thursday as the mid to upper-level trough and associated jet move
away. Also, the low-level moisture is expected to erode once
again. Therefore, mostly fair weather conditions can be expected
with very limited shower activity across interior and western
portions of pr during the afternoon hours. The low-level flow will
be more easterly as a weak surface high pressure builds north of
Long term Friday through Wednesday...
prev discussion... Issued 425 am ast Tue apr 23 2019
a light to moderate easterly wind flow will hold across the
region as the surface high pressure moves eastward over the
western atlantic on Friday. Although a mass of relatively drier|
air will dominate the local weather conditions, showers are
expected to move over portions of eastern puerto rico and the u.S.
Virgin islands during the overnight and morning hours. As the day
progresses, afternoon convection supported by diurnal heating and
local effects is expected to develop over the interior and
western sectors of puerto rico. Ridging aloft will prevent deep
and organized convection to develop, limiting rainfall
accumulations over land.
By Saturday, winds are expected to gradually turn from the
southeast while increasing as the aforementioned high and
associated ridge spreads northeastward across the western and
central atlantic. This flow will aid in advecting deeper tropical
moisture into the region by Sunday, which will hold over the
forecast area through at least Wednesday. Favorable upper level
dynamics resulting from an amplifying trough combined with better
moisture content will enhance the shower activity. Adding to this,
an increase in mid-level moisture content and temperatures around
-8c with divergence aloft will support the likelihood for
isolated thunderstorms across the region, particularly on Sunday
Aviation Sct shra will continue across interior and southern
portions of pr through 23 23z. This activity will produce mount
obsc and could move near tjmz tjps. Brief MVFR conditions should
not be ruled at jps jmz. Brief shra could move near over tist tisx
at times during the rest of the afternoon. Winds will be from the
e to ene between 10-20 knots with higher gusts and sea breeze
variations, becoming calm to light and vrb after 23 23z.
Marine A 4 to 5 foot northeasterly will arrive and spread
across the regional waters by this evening. This will result in
choppy seas of up to 6 feet through Wednesday afternoon. Seas are
expected to improve by Wednesday evening as the swell diminishes.
For beachgoers, as a result of the northeasterly swell, there
will be a high risk of rip currents for the northern beaches of pr
and saint croix through Wednesday.
Preliminary point temps pops
Sju 74 86 74 87 20 20 20 20
stt 73 85 73 85 20 20 20 10
Sju watches warnings advisories
Pr... High rip current risk through late Wednesday night for north
central-northeast-northwest-san juan and vicinity-southeast.
Vi... High rip current risk through Wednesday afternoon for st croix.
Short term... Gl
long term... Previous discussion
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