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 6:12AM||Sunset 5:54PM||Saturday October 19, 2019 6:00 PM AST (22:00 UTC)||Moonrise 10:20PM||Moonset 11:17AM||Illumination 63%|
7 Day Forecast for Marine Location Near Suï¿½rez, PRHourly EDIT Help
Area Discussion for - San Juan, PR  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxca62 tjsj 191731|
area forecast discussion
national weather service san juan pr
131 pm ast Sat oct 19 2019
A tropical wave moving through the area has brought increased
moisture. This will aid in the development of showers and isolated
thunderstorms due to local effects and diurnal heating, especially
in northwestern and interior puerto rico as well as the san juan
metro area. Locally heavy showers across pr could cause localized
flash flooding, and mudslides in areas of steep terrain. Tomorrow
will see development of showers and thunderstorms aided by lingering
moisture over the area. Near normal moisture levels are expected
through much of the week.
Short term Today through Monday...
there is increasing shower development over local caribbean
waters, as well as eastern and interior puerto rico. Additionally,
a line of showers containing thunderstorms has developed downwind
of st. Croix and vieques. The enhanced moisture from the tropical
wave will act to enhance shower and convective development this
afternoon from orographic forcings and diurnal heating. The area
that will be most affected by these showers and isolated
thunderstorms will be northwestern and interior puerto rico, as
well as the san juan metro area, though additional, more isolated,
activity is posible elsewhere. Locally heavy rainfall could cause
urban and small stream flooding, and there is the potential for
mudslides in areas of steep terrain as well.
Tomorrow, winds are forecast to shift to out of the east east-
northeast, under the influence of a low- to mid-level ridge located
to the north-northwest of the local islands. Because of this, the
highest potential for showers and isolated thunderstorms is in
western and interior puerto rico. Lingering moisture from the
tropical wave as it pulls away from the region will aid in the
development of this shower and convective activity, which is
expected to be somewhat limited compared to today. A slight drying
trend is expected for Monday, with mid-level moisture decreasing.
Despite this, there will still be some showers across the area, as
sufficient moisture is carried into the area at low-levels in the
Long term Tuesday through Saturday... From prev discussion...
as previously mentioned, on Tuesday and Wednesday, both a tutt
low and induced surface trough are forecast to develop and move
over the region. The upper trough is forecast to deepen north of
puerto rico on Tuesday, then become a cutoff low as it relocates
just southwest of pr by Wednesday and Thursday. At the same time,|
the surface induced trough is forecast to move over the islands
from the east and increase low level moisture convergence and
instability across the region. The combination of these features
should result in an unsettled weather pattern at least through
Wednesday with good potential for enhanced early morning passing
showers along the coastal areas, followed by enhanced afternoon
convection each day. On Thursday, although the surface trough
will move farther west of the islands, the tutt low is to linger
just southwest of pr and should therefore still provide marginal
instability aloft to support some enhanced afternoon convection.
This should be focused mainly over northwest and the central
interior sections of puerto rico. Isolated to scattered afternoon
showers will also be possible in and around the usvi and the san
juan metro. By Friday, a tropical wave is forecast to enter and
move across the eastern caribbean. At this time model guidance
still suggests that most of the associated moisture and
significant rainfall should pass south of the local islands
through Saturday. However, early morning showers and isolated to
scattered afternoon convection cannot be ruled out each day.
Tempo MVFR to brief ifr conditions due to shra tsra are
possible through 23z at tjsj tjbq tjmz. Across the rest of the
terminals, mainly vcsh vcts is expected. East-southeast winds at 10
to 15 knots with sea breeze variations and higher gusts will prevail
through at least 21z. Light and variable winds are expected
overnight across all terminals.
Marine conditions are expected to continue much as they have, with
wave heights around 5 feet or less. Prevailing winds out of the east
to southeast are forecast to be around 10-15 knots, with higher
gusts. Continuing development of showers and thunderstorms is
expected across regional waters today, enhanced by the passage of a
tropical wave across the caribbean waters.
Preliminary point temps pops
Sju 77 89 78 88 20 20 20 30
stt 78 88 78 88 30 30 30 40
Sju watches warnings advisories
Short term... Ds
long term... .Crs
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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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Wind Forecast for (18,4,5,8)(on/off)  Help
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