Marine Weather and Tides
5/23/2017 - Worked with NOAA again to speed up the 7 day forecast load times. Thanks to them for being responsive.
5/19/2016 - There were issues with the 3 day airport observation history. I switched to another data source. Let me know if you see any issues with the data feeds.
|Sunrise 5:46AM||Sunset 6:55PM||Friday May 26, 2017 10:20 PM AST (02:20 UTC)||Moonrise 6:37AM||Moonset 8:00PM||Illumination 2%|
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|AMZ712 Coastal Waters Of Northern Puerto Rico Out 10 Nm- 901 Pm Ast Fri May 26 2017 |
Rest of tonight..East winds 10 to 15 knots. Seas 3 to 5 feet with occasional seas up to 6 feet. Dominant period 10 seconds. Northeast swell around 4 feet after midnight. Scattered showers through the night.
Saturday..East winds 15 to 20 knots. Seas 3 to 5 feet with occasional seas up to 6 feet. Dominant period 10 seconds. Northeast swell around 4 feet. Scattered showers.
Saturday night..East winds 10 to 15 knots. Seas 3 to 5 feet with occasional seas up to 6 feet. Dominant period 10 seconds. Isolated showers.
Sunday..East winds 15 to 20 knots. Seas 2 to 4 feet with occasional seas up to 5 feet. Dominant period 8 seconds. Isolated showers.
Sunday night..East winds 10 to 15 knots. Seas 2 to 4 feet with occasional seas up to 5 feet. Dominant period 7 seconds. Isolated showers.
Monday..East winds 15 to 20 knots. Seas 3 to 5 feet with occasional seas up to 6 feet. Dominant period 7 seconds. Isolated showers.
Tuesday..East winds 10 to 15 knots. Seas 2 to 4 feet with occasional seas up to 5 feet. Dominant period 8 seconds. Scattered showers. Isolated Thunderstorms.
Wednesday..East winds 15 to 20 knots. Seas 1 to 3 feet. Dominant period 7 seconds. Isolated Thunderstorms. Scattered showers.
|AMZ700 901 Pm Ast Fri May 26 2017 |
Synopsis for puerto rico and the uS. Virgin islands waters... A broad surface high pressure will remain anchored over the central and northeast atlantic through the upcoming weekend. This will result in moderate easterly winds. A tropical wave is forecast to reach the eastern caribbean by early next week. A tutt low is also forecast to develop north and west of the region during this time. This forecast pattern should increase the potential for Thunderstorms across the regional waters as well as increase local winds and seas.
7 Day Forecast for Marine Location Near Carolina, PRHourly EDIT Help
Area Discussion for - San Juan, PR  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxca62 tjsj 270127|
area forecast discussion
national weather service san juan pr
927 pm ast Fri may 26 2017
Update Isolated showers were noted early in the evening hours
across parts of the north central and northwest sections of puerto
rico as well over the yunque area in eastern pr. By 9 pm, most of
the activity had diminished over mainland pr with the exception
of trade wind showers moving over sections of southeastern pr and
across the northern u.S. Virgin islands. The 27 00z tjsj upper air
sounding indicated a moist layer through 12 kft and very dry air
aloft. For the overnight hours into Saturday morning, trade wind
showers can move over land areas of the usvi and eastern pr.
Overnight temperatures are expected to range between the low-mid
60s across the higher elevations to the low-mid 70s across the
coastal areas. No change from previous forecast.
Aviation MainlyVFR expected to prevail overnight across all
terminals. Brief -shra possible at times across the
leeward usvi eastern pr terminals. Latest tjsj sounding indicated
ese winds at 5-17 knots from the surface to fl080.
Marine Buoys across the coastal waters of the islands were
indicating seas between 2-3 feet and east winds at 10-15 knots. No
change from previous discussion.
Prev discussion issued 455 pm ast Fri may 26 2017
synopsis... Weakening ridge aloft and lesser saharan dust across
the region, allowed better transport of trade wind showers and
convective development across the coastal waters and parts of the
islands today. Tutt low and associated trough across the lesser
antilles will lift northwards across the region over the weekend.
Broad high pressure ridge across the central atlantic will hold and
allow better transport of trade wind moisture across the forecast
areas overnight and through the weekend.
Short term... Rest of today through Sunday...
recent satellite imagery and sal products all suggests the saharan
dust has diminished or moved away from the region. The weakening
of the mid to upper level ridge across the region has also allow
for better moisture transport in the easterlies and for afternoon
convective development especially over puerto rico. Expect activity
over land areas to diminish after sunset. However late evening and
overnight passing showers will remain possible over portions of the
coastal waters, with some brushing the east coastal sections some
of the the islands by early morning.
On Saturday through Sunday the gradual increase in the trade wind
moisture will allow for showers and isolated thunderstorm development
each afternoon. The activity however should be focused mainly over
parts of the central interior and west sections of puerto rico. Isolated
streamer like convection will remain possible over the east interior
and parts of the san juan metro each day.
The tutt is expected to lift north and east of the region through Sunday|
while gradually weakening. Conditions aloft should therefore be less
favorable for significant convective development. However, isolated
to scattered afternoon showers will remain likely mainly over western
pr with lesser activity over the adjacent islands and the usvi.
Long term... Monday through Saturday...
tutt low will linger north and east of the region, while a short wave
trough will move eastward across the west and southwest atlantic. The
trough is forecast to become amplified just north and west of the region
Monday through Tuesday of next week. The deepening of this mid to upper
level trough along with the approach of a weak tropical wave will increase
the chance for showers and thunderstorms across the forecast area especially
during the early part of next week. So far models all in agreement on
the increase in precipitable water to near two inches across the area
through Tuesday of next week. This should result in increased potential
for convective development and instability at least until the middle
of next week.
For the rest of the week another surge of saharan dust is expected
to accompany or trail the aforementioned wave. This should allow
for a gradual depletion of the trade wind moisture transport and
thus lesser chance for widespread convection. However, lingering
moisture across the islands as well as the proximity of the upper
trough will allow for afternoon convection each day mainly over
parts of the interior and west sections of puerto rico. By then
only isolated showers are forecast elsewhere.
Aviation... Mtn top obsc observed over the cordillera central of
pr with shra tsra resulting in sct-bkn ceiling btwn fl020-fl080
at tjbq tjmz and possibly at tjsj til 26 23z. Tempo included for
tjmz due to this activity. Elsewhere isold shra psbl at all other
taf sites til 26 23z. Easterly winds 10-15 knots with higher gusts,
bcmg calm to light and variable aft 26 23z.VFR conds durg rmdr
Marine... Mariners can expect seas of 5 feet or less and winds 15
knots or less overnight, but increasing to 15 to 20 knots over
some of the local waters on Saturday. There is a moderate risk of
rip currents for the northwest to northeast beaches of puerto rico,
as well as some of the north facing beaches of culebra and saint
thomas and cramer park in saint croix overnight through Saturday
Preliminary point temps pops
Sju 89 78 90 77 20 40 40 20
stt 88 78 88 77 20 40 40 30
Sju watches warnings advisories
previous discussion... .Ram
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|
|41053 - San Juan, PR||6 mi||50 min||E 7.8 G 9.7||82°F||1017.6 hPa|
|SJNP4 - 9755371 - San Juan, PR||7 mi||50 min||ESE 6 G 6||81°F||83°F||1018.2 hPa|
|FRDP4 - 9753216 - Fajardo, PR||21 mi||50 min||E 8 G 12||82°F||74°F|
|YABP4 - 9754228 - Yabucoa Harbor, PR||29 mi||50 min||ENE 2.9 G 5.1|
|41056||31 mi||80 min||82°F|
|VQSP4 - 9752619 - Isabel Segunda, Vieques, PR||36 mi||50 min||ESE 2.9 G 5.1||80°F|
|ESPP4 - 9752695 - Esperanza, PR||37 mi||50 min||NE 1.9 G 5.1||79°F||84°F||1018 hPa|
|JOXP4 - Jobos Bay Reserve, Puerto Rico||37 mi||95 min||NNE 1.9||80°F||1018 hPa||72°F|
|AROP4 - 9757809 - Arecibo, PR||38 mi||50 min||SSE 2.9 G 4.1||77°F|
|CLBP4 - 9752235 - Culebra, PR||38 mi||50 min||82°F||84°F||1018.2 hPa|
Wind History for San Juan, PR(wind in knots) EDIT (on/off)  Help
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports
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EDIT RT Ports Option Weekend mode (on/off) (on/off)  Help One Week of Data
|Boca De Cangrejos |
Click for Map
Fri -- 04:14 AM AST 0.37 feet Low Tide
Fri -- 05:47 AM AST Sunrise
Fri -- 06:37 AM AST Moonrise
Fri -- 08:59 AM AST 0.90 feet High Tide
Fri -- 03:15 PM AST -0.30 feet Low Tide
Fri -- 06:54 PM AST Sunset
Fri -- 07:59 PM AST Moonset
Fri -- 10:32 PM AST 1.73 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
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|San Juan |
Click for Map
Fri -- 03:50 AM AST 0.18 feet Low Tide
Fri -- 05:47 AM AST Sunrise
Fri -- 06:38 AM AST Moonrise
Fri -- 08:48 AM AST 0.93 feet High Tide
Fri -- 02:56 PM AST -0.45 feet Low Tide
Fri -- 06:55 PM AST Sunset
Fri -- 08:00 PM AST Moonset
Fri -- 10:08 PM AST 1.95 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Weather Map and Satellite Images(on/off)  Help
|Weather Map ||IR Satellite Image from GEOS|
GOES Local Image of Puerto Rico EDIT
Wind Forecast for (22,6,7,8)(on/off)  Help
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The information on this web site has not been checked for accuracy. It is for entertainment purposes only and should be independently verified before using for any other reason. There are five sources. 1) Documents and manuals from a variety of sources. These have not been checked for accuracy and in many cases have not even been read by anyone associated with L-36.com. I have no idea of they are useful or accurate, I leave that to the reader. 2) Articles others have written and submitted. If you have questions on these, please contact the author. 3) Articles that represent my personal opinions. These are intended to promote thought and for entertainment. These are not intended to be fact, they are my opinions. 4) Small programs that generate result presented on a web page. Like any computer program, these may and in some cases do have errors. Almost all of these also make simplifying assumptions so they are not totally accurate even if there are no errors. Please verify all results. 5) Weather information is from numerious of sources and is presented automatically. It is not checked for accuracy either by anyone at L-36.com or by the source which is typically the US Government. See the NOAA web site for their disclaimer. Finally, tide and current data on this site is from 2007 and 2008 data bases, which may contain even older data. Changes in harbors due to building or dredging change tides and currents and for that reason many of the locations presented are no longer supported by newer data bases. For example, there is very little tidal current data in newer data bases so current data is likely wrong to some extent. This data is NOT FOR NAVIGATION. See the XTide disclaimer for details. In addition, tide and current are influenced by storms, river flow, and other factors beyond the ability of any predictive program.