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 5:41AM||Sunset 5:52PM||Saturday March 23, 2019 2:22 PM CST (20:22 UTC)||Moonrise 8:08PM||Moonset 8:53AM||Illumination 92%|
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 231507|
area forecast discussion
national weather service san juan pr
1107 am ast Sat mar 23 2019
Update Showers between st. Thomas and eastern pr lingered
through the late morning hours. Between a quarter to three
quarters of an inch of rain was observed over northeastern pr with
this activity. It was mostly sunny elsewhere across the forecast
area. Steering winds are between 8-12 kt from the southeast. The
sea breeze has already started and low level clouds were
developing along the cordillera central. A mid level trough across
the mona passage and southeast flow east of the region due to a
ridge over the tropical atlantic will aid in the development of
afternoon showers along the interior and west northwest sections
of pr. Moderate to locally heavy showers are possible with this
activity and localized urban and small stream flooding can not be
Aviation MainlyVFR conds expected to prevail across all
terminals. However, shra expected in and around tjsj tjmz tjbq
btw 16z-22z. This could result in tempo MVFR conds. The 23 12z
tjsj upper air sounding indicated ese winds at 7-14 kt blo fl030
and 45 kt at fl120.
Marine Seas will continue to range between 3-5 feet and east-
southeast winds up to 15 knots will prevail across the regional
waters today. Light to moderate showers are expected to continue
through the early afternoon hours between the u.S. Virgin islands
and eastern pr. Additional showers could develop over the west
coast of pr this afternoon. A moderate risk of rip currents will
continue for most of the east and northern beaches of the islands.
Prev discussion issued 556 am ast Sat mar 23 2019
high pressure ridge continued across the tropical atlantic while
an amplifying long wave trough extended southwards across the west
and southwest atlantic. An area of low pressure and associated short
wave trough lingered across the eastern caribbean. In the low levels,
surface high pressure over the central and northeast atlantic,and
a broad surface trough over the eastern caribbean will continue to
promote light to moderate east to southeast winds across the region.
Occasional bands of trade wind moisture will continue to be transported
across the region from time to time through the weekend. Model guidance
continued to suggest a much wetter pattern during the latter part of
next week as the long wave trough pattern is forecast to establish
just north and west of the region.
Short term... Today through Monday...
an occasional patches of moisture are expected to move into the
area through the weekend into early next week. Isolated to scattered
showers will develop during the afternoon as a result of local and
diurnal affects. These showers will produce light to moderate rain
mainly across interior and western areas of puerto rico.
Additionally, an increase in low-level moisture will enhance shower
development during the afternoon. This added moisture comes from
washed out fronts in the central atlantic waters. The arrives to the
area as a result of anticyclonic flow across the atlantic.
A mid-level ridge ridge is forecast to continue to hold over the
region today through early next week. As a result an easterly wind
flow will prevail over the area. As the winds converge over the|
island so will low-level moisture this is depicted by the latest gfs
guidance. The light low-level winds will cause continuous light
showers to re-develop across the area during the afternoon. The tjsj
skew-t shows a moist profile at 1000 to 750 mb, but above the 700 mb
there is a large layer of drier air that will limited the vertical
development of showers. The moisture will be confined to the lower-
level of the atmosphere.
Therefore expect shallow-moisture to increase each day this weekend,
as well as showers across puerto rico and the u.S. Virgin islands.
Guidance shows the mid and upper-levels becoming moist on Sunday and
Monday if this trend continues wetter conditions can be expected for
most of the area.
Long term... Tuesday through Saturday
a lingering short-wave trough over the eastern caribbean will continue
to support moisture pooling across the local region through the middle
of next week. This along with the continued erosion of the upper level
ridge in response to a deep layered long wave trough becoming amplified
across the west and southwest atlantic during the period, will weaken
the trade wind cap inversion and support good tropical moisture transport
and better low level moisture convergence. With that said, expect more
frequent shower development across portions of the islands and coastal
waters beginning late Tuesday and continuing through Saturday.
Model guidance continued to suggest a fairly moist southeast wind flow
to prevail during the period. This along with the proximity of the
amplifying long wave trough just north and west of the region will
support more favorable conditions for convective development with
enhanced shower activity. Guidance also suggest that this deep layered
trough will be strong enough to push a frontal boundary closer to
the local islands. With deeper moisture pooling across the islands and
good upper level dynamics, the environmental conditions will favor
the development of organized and enhanced convection. Will continue
to monitor and see if this unsettled weather scenario unfolds, and
if so the portions of the islands may see some beneficial rainfall
during the period. Stay tuned!!
aviation...VFR conditions will persist across all terminals. Vcsh shra are
forecast to develop across puerto rico terminals by 23 15z, and linger
until 24 00z. Some showers could cause brief mvrf vsbys due to the
shra -shra. Sfc winds will be out of the east to southeast at 10
to 15 kts with sea breeze variations aft 23 14z.
Marine... Seas will range between 1-5 feet across the regional
waters today. However a northerly swell is forecast to arrive and
increase seas to up to 6 feet Sunday through Monday mainly across
the atlantic waters and portions of the local passages. By then,
small craft operators should exercise caution. Overall east to
southeast winds will prevail across the regional waters and
passages through early next week between 10-15 knots.
Preliminary point temps pops
Sju 86 75 87 74 50 40 40 40
stt 85 74 84 75 40 50 50 40
Sju watches warnings advisories
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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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