Marine Weather and Tides
5/20/2018 -- NOAA is having problems with the data feed that I use to draw the graphs. They are aware of the issue and working to resolve it. Sometimes changing the location by about a mile will give a correct graph. 3/3/2018 - There is a new GOES Satellite for the east coast that required rewriting that part of the code. Please report any issues.
|Sunrise 5:56AM||Sunset 7:14PM||Wednesday June 20, 2018 9:37 AM AST (13:37 UTC)||Moonrise 12:49PM||Moonset 12:35AM||Illumination 46%|
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|AMZ741 Mona Passage Southward To 17n- 423 Am Ast Wed Jun 20 2018 |
Today..Southeast winds 10 to 15 knots. Seas 2 to 4 feet with occasional seas up to 5 feet. Dominant period 7 seconds. Numerous showers through the day. Isolated Thunderstorms in the afternoon.
Tonight..Southeast winds 10 to 15 knots. Seas 3 to 5 feet with occasional seas up to 6 feet. Dominant period 7 seconds. Isolated Thunderstorms in the evening. Scattered showers through the night.
Thursday..Southeast winds 10 to 15 knots. Seas 3 to 5 feet with occasional seas up to 6 feet. Dominant period 7 seconds. Isolated showers.
Thursday night..East winds 15 to 20 knots. Seas 3 to 5 feet with occasional seas up to 6 feet. Dominant period 7 seconds.
Friday..East winds 15 to 20 knots. Seas 3 to 5 feet with occasional seas up to 6 feet. Dominant period 7 seconds. Isolated Thunderstorms. Scattered showers.
Saturday..East winds 15 to 20 knots. Seas 4 to 6 feet with occasional seas up to 8 feet. Dominant period 7 seconds. Numerous showers and isolated Thunderstorms.
Sunday..East winds 15 to 20 knots. Seas 4 to 6 feet with occasional seas up to 8 feet. Dominant period 7 seconds. Northeast swell around 4 feet. Isolated Thunderstorms. Scattered showers.
|AMZ700 423 Am Ast Wed Jun 20 2018 |
Synopsis for puerto rico and the uS. Virgin islands waters... A ridge extends from a surface high pressure located across the northeastern atlantic to just north of the local area and will promote moderate southeasterly winds over the next several days. A tropical wave south of the region will brush the area and bring periods of showers and Thunderstorms through Wednesday. NExt tropical wave will approach the regional waters on Friday.
7 Day Forecast for Marine Location Near El Combate, PRHourly EDIT Help
Area Discussion for - San Juan, PR  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxca62 tjsj 200918|
area forecast discussion
national weather service san juan pr
518 am ast Wed jun 20 2018
Synopsis A tropical wave will move out of the area today with
copious moisture and good instability behind it. Drier air will
move in from the east overnight. Another tropical wave will move
through on Friday. Moisture will linger through at least Sunday
morning with scattered showers. More typical weather will follow
next week in east southeast trade wind flow of modest moisture.
Short term Today through Friday...
lingering moisture from a tropical wave that moved to the south of
puerto rico will cause showers and isolated thunderstorms across
most of the area today. A digging tutt low will continue its
southern progression near puerto rico today, and produce upper level
divergence aloft. As a result of the lingering moisture and the
upper level forcing due to the digging tutt low, and a small jet
streak, isolated thunderstorms are expected across most of puerto
rico today. The GFS sounding for san juan depicts how unstable
the current atmosphere is with southerly wind flow, convective temperature
of 88 degrees, and surface based CAPE around 2800, and LI index
of minus 9. Recent analysis of the gdi shows values ranging from
35 to 40 which means there is potential for scattered
thunderstorms with some having the capability of producing heavy
rain and frequent lightning similar yesterday. Therefore, any
additional rainfall could cause urban and small stream flooding
and ponding of water on roadways.
Later tonight the moist tropical air gets eroded away by dry saharan
air filtering in from the east, therefore precipitable water values
are expected to decrease until Friday afternoon, but scattered
showers and isolated thunderstorms are possible across the
northwestern puerto rico.
Friday, will be a transition day from dry saharan air to a moist
tropical air mass as another tropical wave moves through the
caribbean waters Friday morning. Showers and isolated thunderstorms
are expected across the outer caribbean waters and the eastern
islands of puerto before arriving over puerto rico during the
Long term Saturday through Wednesday
moisture from the tropical wave that entered the area Friday will|
continue through Sunday. Then drier air will move in Monday and
Tuesday. Moisture will gradually increase Tuesday through
High pressure at the surface will shift to the west central
atlantic over the weekend. This will cause winds at the surface to
become more easterly and will allow some moderation of the warm
highs that we have had on the north coast of puerto rico.
This trend will continue into the early part of the week.
At upper levels, a tutt low will be just north of puerto rico
beginning Saturday. This indicates thunderstorms with frequent
lightning will be possible. This low will move northwest and will
be replaced by a weak ridge that moves into place between another
stronger low well northeast of the area. This will also allow
showers and thunderstorms to diminish during the early part of
Aviation Vrf MVFR conds will continue for the remainder
of the TAF period. Shra vcts are expected to affect terminals tist
and tisx during the morning before moving across terminals tjsj,
tjps,tjmz and tjbq by 20 14z. Shra tsra will persist until 21 00z
with MVFR vsbys occurring in +shra vcts. Shra tsra will diminish
at all terminals by 21 03z. Sfc winds out of the east south east
at 15 to 20 kts with higher gusts possible within shra tsra.
Marine Seas are relatively low--mostly 5 feet or less until the
weekend. Then seas in the caribbean will have areas of 6 feet.
Small craft advisories are not expected in the next 7 days.
Preliminary point temps pops
Sju 90 77 91 78 50 40 10 20
stt 87 79 89 79 40 20 10 30
Sju watches warnings advisories
Short term... Tw
long term... .Ws
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||0 mi||50 min||82°F||82°F||1016.6 hPa|
|41115 - Rincon, Puerto Rico (181)||40 mi||38 min||83°F||1 ft|
|PTRP4||41 mi||33 min||SSE 1.9 G 5.1||82°F|
|MGIP4 - 9759110 - Magueyes Islands, PR||48 mi||50 min||SE 4.1 G 8.9||83°F||1017.2 hPa|
Wind History for Mayaguez, PR(wind in knots) EDIT (on/off)  Help
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports
Wind History from JMZ (wind in knots)
|1 day ago|
|2 days ago|
EDIT RT Ports Option Weekend mode (on/off) (on/off)  Help One Week of Data
|Mona Island |
Click for Map
Wed -- 12:34 AM AST Moonset
Wed -- 01:34 AM AST 0.72 feet High Tide
Wed -- 05:39 AM AST 0.53 feet Low Tide
Wed -- 05:56 AM AST Sunrise
Wed -- 06:00 AM AST 0.53 feet High Tide
Wed -- 06:52 AM AST First Quarter
Wed -- 11:17 AM AST 0.17 feet Low Tide
Wed -- 12:48 PM AST Moonrise
Wed -- 02:21 PM AST 0.27 feet High Tide
Wed -- 04:03 PM AST 0.25 feet Low Tide
Wed -- 07:09 PM AST Sunset
Wed -- 08:13 PM AST 0.53 feet High Tide
Wed -- 09:56 PM AST 0.51 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
EDIT (on/off)  Help One Week of Data
|Puerto Real |
Click for Map
Wed -- 12:31 AM AST Moonset
Wed -- 01:54 AM AST 1.09 feet High Tide
Wed -- 05:53 AM AST Sunrise
Wed -- 06:52 AM AST First Quarter
Wed -- 08:38 AM AST 0.06 feet Low Tide
Wed -- 12:45 PM AST Moonrise
Wed -- 02:41 PM AST 0.86 feet High Tide
Wed -- 07:06 PM AST Sunset
Wed -- 08:39 PM AST 0.20 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
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.
target = "new">Link to Loop
Other links: Northern Pacific Contential US Full GOES-East
Wind Forecast for (9,2,3,4)(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.