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 6:18AM||Sunset 5:59PM||Thursday October 19, 2017 5:21 AM AST (09:21 UTC)||Moonrise 6:05AM||Moonset 6:11PM||Illumination 1%|
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|AMZ712 Coastal Waters Of Northern Puerto Rico Out 10 Nm- 951 Pm Ast Wed Oct 18 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. Isolated showers.
Thursday..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 in the afternoon. Isolated showers.
Thursday night..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 in the evening. Scattered showers.
Friday..East winds 10 to 15 knots. Seas 3 to 5 feet with occasional seas up to 6 feet. Dominant period 8 seconds. Scattered showers.
Friday night..East winds 10 to 15 knots. Seas 2 to 4 feet with occasional seas up to 5 feet. Dominant period 8 seconds. Isolated showers through the night.
Saturday..East winds 10 to 15 knots. Seas 2 to 4 feet with occasional seas up to 5 feet. Dominant period 8 seconds. Isolated showers.
Sunday..East winds 10 to 15 knots. Seas 3 to 5 feet with occasional seas up to 6 feet. Dominant period 8 seconds. Isolated Thunderstorms, then isolated showers.
Monday..East winds 10 to 15 knots. Seas 2 to 4 feet with occasional seas up to 5 feet. Dominant period 7 seconds. Isolated showers.
|AMZ700 951 Pm Ast Wed Oct 18 2017 |
Synopsis for puerto rico and the uS. Virgin islands waters... Weather conditions will continue to improve as an upper level ridge builds across the region. An increase in winds will produce choppy and dangerous seas across the local waters through at least the weekend, particularly over the offshore caribbean waters and Mona passage. Marine conditions will improve gradually by early next week.
7 Day Forecast for Marine Location Near Lomas, PRHourly EDIT Help
Area Discussion for - San Juan, PR  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxca62 tjsj 190020|
area forecast discussion
national weather service san juan pr
820 pm ast Wed oct 18 2017
Most of the rains have diminished across the islands with a few
areas of showers moving across the offshore waters. As an upper
level ridge continues to build, drier air and hazy skies will
encompass the region. Tranquil conditions will continue overnight
with a few trade wind showers possible across the eastern portions
of the islands on Thursday morning. East southeast winds will
increase on Thursday, resulting in choppy and dangerous marine
conditions and high rip currents along the st croix, vieques and
southern coasts of puerto rico.
MostlyVFR cond will cont across most of the TAF sites during the
rest of the forecast period. Mtn obscuration and ll fg across
portions of pr overnight. For thu, hz will red vis range across
the area. Showers and pos iso t-storms may dev across western pr
with breif periods of MVFR ifr CIGS vsbys in shra tsra. Ese sfc
winds 10-25 kts.
Conditions will continue to improve overnight with only a few
showers lingering across the offshore waters. An increase in winds
will continue to produce choppy and dangerous seas. Seas up to 7
feet and locally higher, as well as winds of 15-25 kts can be
expected. Small craft advisories will continue through at least
the weekend. Also, a high rip current risk is in effect for st.
Croix, vieques and the southern coasts of puerto rico.
Prev discussion issued 329 pm ast Wed oct 18 2017
a tropical wave will continue to move across the region today,
transporting widespread showers and isolated thunderstorms across
the waters and the local islands. As the wave continues to move
westward this evening, weather conditions will improve gradually.
A drier air mass will encompass the region during the next few
days as an upper level ridge will build across the region.
Short term... Today through Friday
variably cloudy skies prevailed across puerto rico and the u.S.
Virgin islands this morning and early this afternoon. Areas of
showers with isolated thunderstorms were observed across the
caribbean coastal waters. Some of this activity moved northwest
affecting the southeast and eastern sections of puerto rico. High
level cloudiness with some hazy conditions prevailed elsewhere.
Very dry weather conditions prevailed across the u.S. Virgin
Showers with isolated thunderstorms will continue to develop
across the caribbean coastal waters with some of this activity
moving inland across the southeast and south sections of puerto
rico. Periods of heavy rainfall can be expected with this
activity. This activity was associated with lingering moisture
of a tropical wave which will continue to move away from the
region the rest of this afternoon and tonight.
A very dry air mass will encompass the region from the east later
this afternoon into this evening as an upper level ridge builds
across the region. As a result, clear to hazy skies are expected
to prevail across the local islands tonight into Thursday. Even
drier weather conditions are expected on Friday, where sju-gfs
computer model forecast precipitable water values as low as 1.0
Long term... Saturday through Thursday...
for Saturday and Sunday, although upper level ridge will hold|
through the weekend, surface will shift more easterly. Trade winds
showers are then expected to affect the local islands from time
to time. The ridge will weaken next Monday into Tuesday as an
upper level trough move in from the east. As a result, a seasonal
weather pattern is then expected across puerto rico and the u.S.
Virgin islands from Thursday through at least next Thursday.
shra vcts with broken to overcast conditions will cont across
most of the TAF sites this aft. Areas of MVFR ifr CIGS vsbys are
likely in shra tsra. Mtn obscuration will continue with ll fg
expected across interior pr overnight. MostlyVFR cond expected
on Thu as drier air moves into the region. E-se sfc winds 10-20
a tropical wave will continue to transport widespread showers and
thunderstorms over the local waters this afternoon and evening.
Weather conditions are expected to improve later tonight.
However, hazardous marine conditions will continue due to seas up
to 7 feet and locally high as well as winds up to 20 kts. Small
craft advisories will continue during the next few days across
most the waters and local passages.
Preliminary point temps pops
Sju 80 87 80 87 20 20 20 20
stt 81 83 81 83 20 20 20 20
Sju watches warnings advisories
Pr... High rip current risk through Friday afternoon for central
interior-northeast-ponce and vicinity-southeast-southwest-
Flash flood watch until 8 pm ast this evening for central
interior-culebra-eastern interior-mayaguez and vicinity-
north central-northeast-northwest-ponce and vicinity-san
juan and vicinity-southeast-southwest-vieques-western
Small craft advisory until 8 am ast Friday for southeast.
Vi... High rip current risk through Friday afternoon for st croix.
Small craft advisory until 8 am ast Friday for st.Thomas... St.
John... And adjacent islands.
Am... High rip current risk through Friday afternoon for coastal
waters of southwestern puerto rico out 10 nm-coastal waters
of southern puerto rico out 10 nm.
Flash flood watch until 8 pm ast this evening for coastal waters
of southwestern puerto rico out 10 nm-coastal waters of
southern puerto rico out 10 nm.
Small craft advisory until 8 am ast Friday for coastal waters of
southern puerto rico out 10 nm-coastal waters of southern
usvi vieques and eastern puerto rico out 10 nm.
Small craft advisory until 8 pm ast Saturday for caribbean
waters of puerto rico from 10 nm to 17n-mona passage
southward to 17n.
Small craft advisory until 2 pm ast Friday for anegada passage
southward to 17n-atlantic waters of puerto rico and usvi
from 10 nm to 19.5n.
Short term... Ac
long term... .99
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||16 mi||52 min||ESE 9.7 G 14||82°F||1014 hPa|
|SJNP4 - 9755371 - San Juan, PR||16 mi||52 min||83°F||1015.1 hPa|
|YABP4 - 9754228 - Yabucoa Harbor, PR||16 mi||52 min||85°F|
|41056||25 mi||82 min||E 18 G 21||83°F||5 ft||1014.7 hPa (-1.0)|
|CLBP4 - 9752235 - Culebra, PR||33 mi||52 min||82°F||84°F||1015.1 hPa|
|AROP4 - 9757809 - Arecibo, PR||43 mi||52 min||SE 1.9 G 4.1|
|42085 - Southeast of Ponce, PR||43 mi||82 min||ENE 19 G 25||85°F||84°F||1013 hPa (-1.0)|
Wind History for Fajardo, 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||11 mi||26 min||E 7||6.00 mi||Partly Cloudy with Haze||81°F||77°F||88%||1014.9 hPa|
Wind History from JSJ (wind in knots)
|1 day ago||Calm||Calm||SE||E||E||E||E||E||E||E||SE||E||E||E||E||E||E||SE||SE||Calm||Calm||E||Calm|
|2 days ago||SE||Calm||S||Calm||W||E||Calm||Calm||E||SE||SE||SE||S||SE||S|
EDIT RT Ports Option Weekend mode (on/off) (on/off)  Help One Week of Data
|Boca De Cangrejos |
Click for Map
Thu -- 02:34 AM AST 0.05 feet Low Tide
Thu -- 06:05 AM AST Moonrise
Thu -- 06:19 AM AST Sunrise
Thu -- 09:09 AM AST 1.40 feet High Tide
Thu -- 03:12 PM AST New Moon
Thu -- 03:29 PM AST 0.21 feet Low Tide
Thu -- 05:58 PM AST Sunset
Thu -- 06:11 PM AST Moonset
Thu -- 09:08 PM AST 1.05 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
EDIT (on/off)  Help One Week of Data
|Vieques Passage |
Click for Map
Thu -- 01:21 AM AST -0.00 knots Slack
Thu -- 04:24 AM AST -0.60 knots Max Ebb
Thu -- 06:03 AM AST Moonrise
Thu -- 06:17 AM AST Sunrise
Thu -- 07:18 AM AST 0.00 knots Slack
Thu -- 10:36 AM AST 0.74 knots Max Flood
Thu -- 01:45 PM AST -0.00 knots Slack
Thu -- 03:12 PM AST New Moon
Thu -- 05:06 PM AST -0.81 knots Max Ebb
Thu -- 05:57 PM AST Sunset
Thu -- 06:10 PM AST Moonset
Thu -- 08:36 PM AST 0.00 knots Slack
Thu -- 11:19 PM AST 0.52 knots Max Flood
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 (5,6,7,8)(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.