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.
6/2/2019. Many thanks to a user for reporting an error on one of the Edit pages. The switch to PHP 7.2 caused many pages that previously worked to quit working. I fixed many but I still depend on users to report ones I missed. Please report errors HERE or send an email to me at L-36.com. Allen
|Sunrise 6:28AM||Sunset 6:07PM||Tuesday October 22, 2019 8:03 PM AST (00:03 UTC)||Moonrise 12:43AM||Moonset 2:10PM||Illumination 31%|
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 221734|
area forecast discussion
national weather service san juan pr
134 pm ast Tue oct 22 2019
Showers and thunderstorms have developed over interior and
southwestern puerto rico, with locally heavy rain; further
development is possible through the afternoon. Streamers have
also developed off of the major islands to the east of mainland
puerto rico. Tomorrow, a similar pattern is expected, but with
increased instability and therefore a higher potential for more
thunderstorms, as well as more widespread showers. Additionally,
the mean flow over the area is expected to shift to more easterly,
which could shift the location of the maximum shower activity to
be more in western puerto rico than southwestern, though other
areas will still likely see showers. There is the potential for
urban and small stream flooding associated with this shower and
convective activity for the next couple of days. During the
overnight hours into the morning, scattered showers, especially
over the waters and northern northeastern puerto rico, are
anticipated, and there is the potential for isolated
Short term Today through Tuesday...
this afternoon, a tutt stretching across the region from the
northeast is in the process of forming a cutoff upper level low.
This low will begin to make its way to the southwest to over or just
south of hispaniola. While this will likely not have a significant
impact on conditions this afternoon, it is anticipated to cause
increased instability, and thus enhance shower and convective
activity as it moves away to the west. This afternoon will see
continuing development of showers and thunderstorms, especially in
southwestern and interior puerto rico; there is a continuing risk
of locally heavy rainfall and the potential for urban and small
stream flooding. Tonight is forecast to be similar to last night,
with popcorn showers over the waters, and some showers in northern
and northeastern puerto rico, as well as some over the u.S.
Virgin islands. Tomorrow, winds are expected to veer to out of the
east during the day. With the enhanced instability, and
continuing near-normal levels of moisture over the region, an
increase in shower and thunderstorm activity from local effects
and daytime heating is forecast for the afternoon. Western and
interior puerto rico are likely to see the highest level of
activity, but other areas will still have a good chance to see at
least some showers on the day.
The effects of the upper level low will continue over the area on
Thursday, and therefore showers and thunderstorms are likely again;
with the low moving away, however, this activity is expected to
decrease somewhat. With winds forecast to be out of the east southeast,
the maximum activity will likely be in western, northwestern, and
interior puerto rico.
Long term Friday through Tuesday... From prev discussion...
a relatively moist weather pattern is expected through at least
midday Monday with near-average GFS model-estimated precipitable|
water vapor values between 1.6 and 2.0 inches holding across the
region. On Friday, the combination of lingering moisture from a
departing surface induced trough and somewhat favorable conditions
aloft due to a meandering tutt low to the northwest will support
a generally convective pattern. Then, a meandering surface high
pressure over north atlantic will drive the remnants of a frontal
boundary into the local area by Saturday and Sunday. Another
surface induced trough is forecast to move into the region late
Sunday into Monday, increasing low-level convergence and bursting
precipitable water vapor values over 2.0 inches. Thereafter, a
gradual drying trend is expected and local weather conditions will
depend in the timing of trade wind patches of dry and moist air
moving across the forecast area from the east-northeast. In the
meantime, another cutoff tutt low is forecast to approach the
northeastern caribbean from the east. The convergent subsidence
side of the latter will move over the forecast area on Monday and
Tuesday, resulting in unfavorable conditions aloft and limiting
shower and thunderstorm development across the region.
Shra tsra expected across portions of interior, western,
and southern pr through 22 22z, affecting the vicinity of tjmz tjps.
Tempo MVFR conditions are possible. Elsewhere, sct shra could result
in vcsh at times across the leeward islands, usvi, and tjsj
terminals. However, no significant impacts to operations are
expected at this time. Low-level winds will continue out of the ene
between 10 and 15 kts with sea breeze variations through 22 22z,
becoming light and variable overnight.
Relatively tranquil seas are expected to continue through the week
and into the weekend, with wave height below 5 feet. Prevailing
winds persist out of the northeast east-northeast today, veering to
more easterly tomorrow, with speeds up to 15 knots. Showers and
isolated thunderstorms will continue this afternoon, especially
around southwestern puerto rico and downwind of the major islands
east of mainland puerto rico. Tonight into tomorrow morning, popcorn
showers are expected over the waters, similar to this morning.
Showers and isolated thunderstorms are likely again each afternoon
for the next few days. There remains a low to moderate risk of rip
currents at north-facing beaches of puerto rico, culebra, and st.
Thomas today, as well as tomorrow.
Preliminary point temps pops
Sju 88 77 88 77 60 60 50 50
stt 88 78 87 77 30 30 60 60
Sju watches warnings advisories
Short term... Gl
long term... .Crs
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||45 min||81°F||86°F||1013 hPa|
|MGZP4 - 9759394 - Mayaguez, PR||88 mi||51 min||86°F||1013.2 hPa|
Wind History for Mayaguez, PR(wind in knots) EDIT (on/off)  Help
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports. Follow links for more data.
|Aquadilla, Rafael Hernandez Airport, PR||78 mi||73 min||SE 8||10.00 mi||Thunderstorm in Vicinity||79°F||71°F||79%||1012.9 hPa|
Link to 5 minute data for TJBQ
Wind History from JBQ (wind in knots)
|1 day ago||S||SE||Calm||SE||SE||SE||E||E||E||E|
|2 days ago||Calm||SE||SE||E||E||E||NE||NE||E|
EDIT Weekend mode (on/off) (on/off)  Help One Week of Data
EDIT (on/off)  Help One Week of Data
Weather Map(on/off)  Help Weather Map
GEOS 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 (20,4,5,8)(on/off)  Help
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