Marine Weather and Tides
6/25/2017 - NOAA is having a major issue that impact the 7 day forecast load times. Many users are reporting problems. The issue has been reported.
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 6:31AM||Sunset 5:46PM||Monday November 20, 2017 9:42 AM AST (13:42 UTC)||Moonrise 8:11AM||Moonset 7:40PM||Illumination 3%|
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|AMZ735 Coastal Waters Of Southern Puerto Rico Out 10 Nm- 358 Am Ast Mon Nov 20 2017 |
Today..East winds 5 to 10 knots. Seas 1 to 3 feet. Dominant period 8 seconds. Scattered showers.
Tonight..East winds 10 to 15 knots. Seas 1 to 3 feet. Dominant period 8 seconds. Isolated showers.
Tuesday..East winds 10 to 15 knots. Seas 2 to 4 feet with occasional seas up to 5 feet. Dominant period 7 seconds. Isolated showers.
Tuesday 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.
Wednesday..East winds 10 to 15 knots. Seas 1 to 3 feet. Dominant period 7 seconds. Isolated showers.
Thursday..East winds 5 to 10 knots. Seas 1 to 3 feet. Dominant period 8 seconds. Isolated showers.
Friday..East winds 5 to 10 knots. Seas 1 to 3 feet. Dominant period 8 seconds. Isolated showers.
|AMZ700 358 Am Ast Mon Nov 20 2017 |
Synopsis for puerto rico and the uS. Virgin islands waters... A shear line and associated moisture will continue to linger across the local atlantic waters today. This will result in periods of showers and Thunderstorms over the local waters. Easterly winds and a more stable air mass are expected across the local waters on Tuesday.
7 Day Forecast for Marine Location Near Emajagua, PRHourly EDIT Help
Area Discussion for - San Juan, PR  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxca62 tjsj 200830|
area forecast discussion
national weather service san juan pr
430 am ast Mon nov 20 2017
Synopsis A shearline just to the northwest of the local area is
now dissipating, but above normal moisture will remain over the
local area today. Winds will be southeasterly today but will turn
easterly as a surface high pressure moved over the western
atlantic, north of the local islands. Showers and thunderstorms
are expected today, however, upper ridge will dominate the local
area starting on Tuesday, stabilizing the local atmosphere just
as drier air moves in, which will cause a decrease in shower and
thunderstorm activity, even after moisture increases slightly on
Wednesday since the upper ridge will remain for the next several
Short term Today through Wednesday...
mostly cloudy skies prevailed across the forecast
area overnight and early this morning. Showers were observed
across the local waters but none over land areas. Coastal
temperatures were in the mid to upper 70s under light and variable
Lingering moisture associated with a dissipating shear line will
continue to prevail across the local isles today. Although latest
guidance continues to suggest precipitable water decreasing somewhat
across the area as well as less coverage of showers and
thunderstorms, there still a high chance for showers thunderstorms
to form in the southeasterly flow off of EL yunque and into the san
juan metro area and over the northwest quadrant of puerto rico. Due
to already saturated soils, any prolonged period of heavy rainfall
will result urban flooding and sharp rises along small streams and
rivers as well as mudslides in areas of steep terrain. Although a
mid to upper level ridge will build across the forecast area and
hold through the forecast period, easterly winds will continue to
bring patches of low level moisture to keep the chance of passing
showers Tuesday and Wednesday. Therefore, expect a seasonable
weather pattern with passing showers across usvi and E pr as well as
limited shower activity across west puerto rico both days.
Long term Thursday through Tuesday...
late in the workweek into early next week, the available moisture
will be rather variable, with patches of moisture and patches of|
drier air moving through the local area generally speaking. There
will be a day with near normal moisture then a day with lower
moisture followed by higher moisture. This pattern of somewhat
patchy moisture normally causes brief and isolated showers in
the morning and overnight hours with locally induced showers in
the afternoon but generally not very intense or widespread, which
will likely be the case late this week and at least into the
weekend since an upper high pressure is expected to prevail over
the local area. The expected equivalent potential temperature
indicates mostly stable conditions as well, therefore at this
time we expect some but not much weather late this week into
early next week.
Aviation MostlyVFR conds expected through 20 16z. Shra tsra
expected in the afternoon to result in MVFR conds in and around
jsj jbq and jmz through 20 22z. Elsewhere vcsh expected. Ese winds
at around 10 knots with some sea breeze variations, becoming light
and variable overnight.
Marine Seas of 3 to 5 feet are expected today across the local
waters for the next few days. Winds will be up to 10 knots today
from the southeast, increasing to up to 15 knots from the east on
Tuesday and for the next several days after that. There is a
moderate risk of rip currents today along the northeast, north and
northwest coast of mainland puerto rico and culebra. Small
sections in southwest puerto rico also has a moderate risk of rip
currents as well as the northern and eastern beaches of vieques,
the north and northwest beaches of saint tomas and cramer park in
Preliminary point temps pops
Sju 86 76 90 76 50 20 20 20
stt 85 76 86 77 50 20 20 30
Sju watches warnings advisories
Pr... Flash flood watch until 2 pm ast this afternoon for northwest-
Short term... Om
long term... .Ja
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|
|YABP4 - 9754228 - Yabucoa Harbor, PR||5 mi||42 min||82°F|
|JOXP4 - Jobos Bay Reserve, Puerto Rico||18 mi||57 min||ENE 1.9||82°F||1014 hPa||77°F|
|41056||29 mi||102 min||SE 5.8 G 7.8||82°F||3 ft||1012.5 hPa (+1.7)|
|SJNP4 - 9755371 - San Juan, PR||34 mi||42 min||83°F||1013.5 hPa (+2.1)|
|42085 - Southeast of Ponce, PR||35 mi||102 min||NNE 9.7 G 14||82°F||83°F||1011.6 hPa (+1.8)|
|41053 - San Juan, PR||35 mi||42 min||SSE 5.8 G 7.8||81°F||83°F||5 ft||1012.6 hPa (+2.1)|
|CLBP4 - 9752235 - Culebra, PR||37 mi||42 min||84°F||83°F||1013.7 hPa (+2.3)|
Wind History for Yabucoa Harbor, PR(wind in knots) EDIT (on/off)  Help
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports
|San Juan, Luis Munoz Marin International Airport, PR||30 mi||1.8 hrs||S 3||10.00 mi||Partly Cloudy||79°F||77°F||94%||1012.9 hPa|
Wind History from JSJ (wind in knots)
|1 day ago||SE||E||E||SE||S||Calm||N||NE||S||Calm||Calm||Calm||Calm||Calm||SE||SE||Calm||SW||Calm||SW||Calm||SE||Calm|
|2 days ago||S||SE||SE||S|
EDIT RT Ports Option Weekend mode (on/off) (on/off)  Help One Week of Data
|Puerto Maunabo |
Click for Map
Mon -- 02:15 AM AST 0.02 feet Low Tide
Mon -- 06:32 AM AST Sunrise
Mon -- 08:10 AM AST Moonrise
Mon -- 10:22 AM AST 0.77 feet High Tide
Mon -- 05:46 PM AST Sunset
Mon -- 07:40 PM AST Moonset
Tide / Current data from XTide NOT FOR NAVIGATION
EDIT (on/off)  Help One Week of Data
|Vieques Passage |
Click for Map
Mon -- 12:30 AM AST 0.44 knots Max Flood
Mon -- 03:23 AM AST -0.00 knots Slack
Mon -- 05:58 AM AST -0.37 knots Max Ebb
Mon -- 06:31 AM AST Sunrise
Mon -- 08:09 AM AST Moonrise
Mon -- 08:25 AM AST 0.00 knots Slack
Mon -- 11:58 AM AST 0.70 knots Max Flood
Mon -- 03:08 PM AST -0.00 knots Slack
Mon -- 05:44 PM AST Sunset
Mon -- 06:44 PM AST -0.88 knots Max Ebb
Mon -- 07:39 PM AST Moonset
Mon -- 10:34 PM AST 0.00 knots Slack
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 (8,2,3,4)(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.