Marine Weather and Tides
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|Sunrise 6:05AM||Sunset 6:22PM||Sunday September 15, 2019 9:08 PM AST (01:08 UTC)||Moonrise 7:32PM||Moonset 7:07AM||Illumination 96%|
7 Day Forecast for Marine Location Near Su�rez, PRHourly EDIT Help
Area Discussion for - San Juan, PR  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxca62 tjsj 160103|
area forecast discussion
national weather service san juan pr
903 pm ast Sun sep 15 2019
Update Moisture was a little better than this morning's
sounding, but a little less than 24 hours ago. The 16 00z
sounding showed 2.18 inches of precipitable water. Nevertheless
it was unstable with a lifted index of minus 7 and a surface based
cape of over 3600, hence showers have been developing offshore of
eastern puerto rico and rolling into the area. Some showers are
even along the northwest coast. At 16 0030z some lightning was
being observed in naguabo, rio grande and the waters north of
vieques. Thunderstorms are expected to end after midnight.
Currently puerto rico and the u.S. Virgin islands are in the most
favorable precipitable water. The dry slot should arrive before
the night is over, but may not have much less than 1.7 inches of
precipitable water. The next mass of moisture better than 2
inches is associated with the wave and was moving into the leeward
and windward island as of 15 23z. There are thunderstorms
associated with this last band, but they are northeast of the
leeward islands. The band of moisture and the axis of the tropical
wave is expected to enter the forecast area this afternoon and
spread over puerto rico overnight Monday night with more showers
Aviation Brief MVFR ifr will diminish aft 16 04z for ERN pr.
Shra and mtn obscurations will likely continue in ERN pr thru
16 13z. Aft 16 16z shra tsra will dvlp in WRN and interior pr with
areas of MVFR ifr and mtn obscurations. Shra and psbly tsra will
continue in the ERN half of the fcst area past 17 04z. Sfc winds
10-20 mph from the E with land sea breeze variations. MAX winds
less than 20 kt blo fl540 til 16 21z.
Marine Across the regional waters, mariners will find seas up to 5 feet
and winds up to 17 knots both tonight and Monday. Hazardous seas
are expected to come in from the northern quadrant Tuesday through
In the surf zone, there is a moderate risk of rip currents for
most of the local beaches of the north, southeast portions of
puerto rico tonight. Also coasts on the northeast of culebra and
southeast and east side of vieques will have a moderate risk. A
high risk of rip currents will develop on Monday night into Tuesday
for coasts with a northern exposure.
Prev discussion issued 152 pm ast Sun sep 15 2019
synopsis... Surface high pressure in the atlantic, north of the
local area will provide a moderate easterly wind flow for the next
several days, becoming east to east southeast for the latter part
of the workweek. A weak tropical wave is moving across the local
area today, then slightly drier air will move in on Monday, but
another tropical wave will pass late on Monday into Tuesday,
causing an increase in moisture once again.
Short term... This afternoon through Tuesday.
Showers and thunderstorms are expected to continue this afternoon
across western pr through the late afternoon hours. Meanwhile
scattered showers with isolated thunderstorms are expected across
eastern pr, usvi and the local waters around the usvi and south of
puerto rico. Scattered to numerous showers with isolated
thunderstorms are expected across the local waters, usvi and
eastern pr overnight as the tropical wave continues to move|
through the local area. The drier air expected on Monday will
bring a decrease in shower activity through the day, but central
and western pr could observe rainfall and thunderstorms due to
local effects. Another tropical wave will be moving in late Monday
into Tuesday, bringing moisture to the local area. This will also
bring showers and thunderstorms across the usvi and eastern pr in
the morning on Tuesday then the activity will move west, affecting
the caribbean waters as well as western pr in the afternoon.
Long term... Wednesday through Sunday...
from previous discussion...
a dry saharan air mass will hold across the region through
Wednesday, and cause precipitable waters to rapidly decline. In
addition, the dry saharan air will limit the development of
widespread showers and thunderstorms, however, showers and
isolated thunderstorms will develop as a result of local and
diurnal effects. Mid-day Thursday a weak tropical wave will push
into the region from the east and increase low-level moisture, and
showers and thunderstorms. This wave is expected to quickly race
off to the west leaving behind some residual moisture on Friday.
Saturday, another tropical wave is forecast to transverse the
region, and increase showers and thunderstorms just like the
previous tropical wave. The tropical wave will exit to the west
late Sunday, but the wave will continue to pull moisture from deep
tropics across puerto rico and adjacent islands. The deep
tropical moisture coupled with significant heating and local
effects will induce showers and thunderstorms through the
beginning of the workweek.
Aviation... Tsra will be possible across tncm tkpk through 15 22z,
resulting in MVFR conditions at times. Shra tsra expected across
western pr through 15 22z, affecting mainly tjmz terminal with
possible MVFR conditions. Otherwise, mainlyVFR conditions should
prevail across the local terminals throughout the period. Winds will
continue from the E between 10 and 20 knots with higher gusts and
sea breeze variations through 15 22z, becoming light and variable
Marine... The tropical wave passing through will cause seas to
become a bit choppy, up to 5 feet, with winds will ranging mostly
from 10 to 15 knots, up to 20 across the nearshore caribbean.
Showers and thunderstorms are expected across the local waters
this afternoon and tonight. A moderate risk of rip currents for
the northern, southwestern, and southeastern beaches of puerto
rico. There is a moderate risk of rip currents across many of our
local beaches, otherwise a low risk is expected.
Preliminary point temps pops
Sju 80 90 79 91 50 50 50 30
stt 80 90 81 90 60 60 60 20
Sju watches warnings advisories
Short term... Ws
long term... .Icp
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