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 6:36AM||Sunset 6:45PM||Wednesday March 20, 2019 5:08 PM AST (21:08 UTC)||Moonrise 6:36PM||Moonset 6:25AM||Illumination 100%|
7 Day Forecast for Marine Location Near Rinc�n, PRHourly EDIT Help
Area Discussion for - San Juan, PR  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxca62 tjsj 202025|
area forecast discussion
national weather service san juan pr
425 pm ast Wed mar 20 2019
Synopsis Ridge aloft will continue to maintain a fairly stable
weather pattern across the forecast area with limited shower
activity expected through the end of the work week. Surface high
pressure across the northeast atlantic and a frontal boundary over
the western atlantic will continue to maintain a moderate east to
southeast wind flow during the next several days.
Short term Today through Friday...
very dry air above 700 mb as a result of a ridge aloft will
continue to suppress the development of deep convection and
therefore, the chances of significant rainfall activity to
materialize during the short term period.
Currently, a surge in low-level is moving through the area and has
resulted some limited shower activity across portions of interior
and northwest pr as well as near the vicinity of vieques and
coastal areas of northeast pr during the afternoon hours.
However, given the hostile environmental conditions in place
aloft, most of the these showers were light to moderate in
intensity. As a result, rainfall accumulations generally remained
under a quarter of an inch.
Later tonight into the day on Thursday, an area of drier air will
be moving over the region with precipitable water values expected
to drop below 1 inch. Therefore, less cloud cover and mostly dry
conditions can be expected across most of the region. A few
showers, however, cannot be ruled out during the afternoon hours
across the northwest quadrant of pr. These showers should be brief
and only result in very light rainfall accumulations.
Another surge in low-level moisture is expected by tomorrow night
into the day on Friday with precipitable water values rising
to between the 1.2 to 1.4 range. This would increase the low-
level cloudiness and shower activity once again. Some scattered
showers are possible across portions of eastern pr, the usvi, and
surrounding waters during the overnight and morning hours followed
by the development of locally and diurnally induced activity
across the northwest quadrant of pr during the afternoon hours.
Long term Saturday through Thursday...
issued 411 am ast Wed mar 20 2019
for the weekend, drier than normal air will return briefly on
Saturday, but another patch of moisture could move in late in the
night on Saturday into Sunday but not enough to cause any|
significant amounts of rain. Even though some showers are
expected to develop across the western sections of pr in the
afternoon hours, these are not expected to be too significant. A
frontal boundary is still forecast to stay well north northwest of
the local islands, but the latest guidance has some moisture
pooling just west of the local islands on Sunday into Monday,
which could bring more significant moisture than previously
expected, but at this time the more significant rain is expected
to be just west of pr across the local waters. Long range models
are showing a surface high pressure move through the western
atlantic into the central atlantic by Monday, then a surface low
to move across the eastern seaboard of the us on Tuesday and
through midweek, causing southeasterly winds locally and possibly
dragging some moisture from the south and over the local islands,
but the mid and upper levels for those days are still not looking
favorable for prolonged and significant vertical development of
showers. The model solutions have some rainfall accumulations but
less than you would expect given the amount of moisture that it
puts over the local area with the GFS model having close to 2
inches of precipitable water. Confidence is low this far out in
the forecast, the models have changed slightly over the past few
days, but have been consistent in bringing good moisture to the
local area by midweek next week.
Aviation Advective or locally induced showers will bring sct
occasional bkn between fl040-fl060 and vcsh to tjsj, tjbq, tjmz,
and tjps through at least 20 23z. This may result in brief MVFR
conditions. Ese winds of 10-15 kts with occasional higher gusts up
to 20 knots will continue, becoming light and variable after
Marine Fairly tranquil marine conditions with seas generally
below 5 feet and east to southeast winds up to 15 knots are expected
to continue during the next few days. A moderate risk of rip
currents is expected for portions of the north-facing beaches of
pr and culebra on Thursday.
Preliminary point temps pops
Sju 74 88 74 88 20 20 30 30
stt 74 85 74 85 20 30 30 20
Sju watches warnings advisories
Short term... Gl
long term... .From previous discussion
Weather Reporting StationsEDIT (on/off)  Help NOTE: Click on distance to see the station location on a map
|Stations||Dist||Age||Wind||Air Temp||Water Temp||Waves||Pressure||DewPt|
|MISP4 - 9759938 - Mona Island, PR||70 mi||39 min||80°F||82°F||1014.1 hPa|
|MGZP4 - 9759394 - Mayaguez, PR||88 mi||45 min||80°F||81°F||1013.8 hPa|
Wind History for Mayaguez, PR(wind in knots) EDIT (on/off)  Help
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports
|Aquadilla, Rafael Hernandez Airport, PR||78 mi||74 min||N 4||10.00 mi||Overcast||79°F||66°F||65%||1012.9 hPa|
Wind History from JBQ (wind in knots)
|1 day ago||NE||E||E||SW||SE||SE||E||SE||E|
|2 days ago||E||NE||NE||E||S||SW||Calm||Calm||S||SE||SE||NE||N||N||N||N||NE||N||NE |
EDIT RT Ports Option Weekend mode (on/off) (on/off)  Help One Week of Data
EDIT (on/off)  Help One Week of Data
Weather Map and Satellite Images(on/off)  HelpWeather Map
GOES Local Image of Puerto Rico EDIT
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.
Link to Loop
Other links: Northern Pacific Contential US Full GOES-East
Wind Forecast for (17,4,5,8)(on/off)  Help
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