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 6:17AM||Sunset 5:57PM||Friday October 20, 2017 12:22 PM AST (16:22 UTC)||Moonrise 6:54AM||Moonset 6:49PM||Illumination 0%|
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|AMZ725 Coastal Waters Of Southern Usvi Vieques And Eastern Puerto Rico Out 10 Nm- 957 Am Ast Fri Oct 20 2017 |
Rest of today..East winds 10 to 15 knots. Seas 3 to 5 feet with occasional seas up to 6 feet. Dominant period 8 seconds. Isolated showers.
Tonight..East winds 10 to 15 knots. Seas 3 to 5 feet with occasional seas up to 6 feet. Dominant period 8 seconds. Isolated showers.
Saturday..East winds 10 to 15 knots. Seas 3 to 5 feet with occasional seas up to 6 feet. Dominant period 7 seconds. Isolated showers through the day.
Saturday night..East winds 15 to 20 knots. Seas 4 to 6 feet with occasional seas up to 8 feet. Dominant period 7 seconds. Isolated showers.
Sunday..East winds 15 to 20 knots. Seas 4 to 6 feet with occasional seas up to 8 feet. Dominant period 7 seconds. Isolated showers.
Monday..East winds 10 to 15 knots. Seas 2 to 4 feet with occasional seas up to 5 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 8 seconds. Isolated showers.
|AMZ700 957 Am Ast Fri Oct 20 2017 |
Synopsis for puerto rico and the uS. Virgin islands waters... A trade wind surge will continue to produce choppy and hazardous seas particularly across the offshore caribbean waters and local passages through at least Sunday. Saharan dust over the local area will continue to cause reduced visibility due to haze today. A moderate to fresh easterly wind flow will prevail Sunday and into early next week.
7 Day Forecast for Marine Location Near Vieques, PRHourly EDIT Help
Area Discussion for - San Juan, PR  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxca62 tjsj 201523|
area forecast discussion
national weather service san juan pr
1123 am ast Fri oct 20 2017
Update The 12z tjsj sounding came in very dry with pwat values
of near 1 inch, which is more than 2 standard deviations below
normal according to sounding climatology for october. This dry air
mass will continue to support mostly fair weather conditions
across the region throughout the day today into tonight. There is
a slight chance that a few locally and diurnally induced showers
may still develop across western pr this afternoon, however, given
how dry the atmosphere is any showers that do develop will be
short-lived with no significant accumulations expected. It will
also continue to be hazy as saharan dust particulates remain over
Aviation MostlyVFR conditions will continue to prevail across
all terminals. A brief reduction to MVFR conditions due to hazy
conditions still possible with improvement expected this afternoon
and tonight. Some brief MVFR conditions may also occur in any
showers that manage to develop in the vicinity of tjbq and tjmz
this afternoon. E-se winds of 10-15kt with gusts up to 20kt
expected through this afternoon. Winds diminishing below 10 kts
after 21 00z.
Marine No changes to previous discussion. Small craft
advisories continue in effect across the nearshore and offshore
caribbean waters and mona passage with seas as high as 7 feet
possible. Up to 5-6 feet expected across the rest of the local
waters. High risk of rip currents continue across southwest and
southeast coast of pr through this afternoon with low to moderate
Prev discussion issued 458 am ast Fri oct 20 2017
synopsis... The dry airmass will continue through Monday, but
afternoon scattered showers are expected in western puerto rico
by Sunday. Moisture will continue to increase during the week next
week and the chances for showers will follow.
Short term... Today through Sunday...
the lower levels of the atmosphere continue unseasonably dry
while ridging aloft also generates subsidence today and Saturday.
Nevertheless some patches of modest moisture will travel west
across the local atlantic waters bringing a slight increase in
isolated showers and cloud cover Saturday and a little more on
Sunday, such that even the precipitable water spikes to 1.5
inches Sunday morning. It returns to less than one inch according
to the GFS Sunday afternoon. Also on Sunday an upper level low
will begin to drop southeast toward the leeward islands,
increasing northwest flow at upper levels over the local area.
Generally however upper levels contribute little or nothing to
support convection and mid levels remain very dry through Sunday|
evening. This is expected to suppress all deep convection in the
Long term... Monday through Thursday
the upper level low that was sinking southeast toward the leeward
islands will pull a 60 to 70 knot jet over the area on its western
side by Tuesday, but divergence convergence remains mainly
neutral at upper levels even as moisture slowly increases through
the week. This will bring a gradual increase in showers Wednesday
through Saturday and eventually late in the week, thunderstorms
will also return. Flow will oscillate between east northeast and
east southeast as weak troughs pass through from the east Tuesday
and Friday night of the upcoming week and generally moisture will
be best following the waves when convection will favor the
northwest quarter of puerto rico. Strong features or tropical
cyclone development is not indicated during the next 7 to 10 days.
Aviation... Current visibilities range from almost 4 miles to
around 8 miles as a strong dust episode continues. Condtions will
gradually improve during the next 24 hrs. But areas of MVFR due
to dust will continue. Shra will be few--if any. Sfc winds ese 10
to 20 kt with higher gusts and sea breeze influences. Winds just
above the sfc to fl100 ese 20 to 30 kt bcmg just 20 kt 21 00-12z.
This will also be the level of maximum winds through 21 06z.
Marine... Winds and seas will slowly diminish during the next
several days but a second weak wave will increase seas again on
Sunday--mainly in the caribbean. Small craft advisories will
continue there till Monday.
Preliminary point temps pops
Sju 89 79 89 80 0 10 20 10
stt 88 80 88 80 0 20 20 10
Sju watches warnings advisories
Pr... High rip current risk until 6 pm ast this evening for central
Small craft advisory until 6 pm ast this evening for southeast.
Am... High rip current risk until 6 pm ast this evening for coastal
waters of southwestern puerto rico out 10 nm.
Small craft advisory until 6 pm ast this evening for coastal
waters of southern puerto rico out 10 nm.
Small craft advisory until 6 pm ast Sunday for caribbean waters
of puerto rico from 10 nm to 17n-mona passage southward to
Short term... Gl
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|
|41056||8 mi||143 min||E 14 G 18||83°F||3 ft||1016.7 hPa (+1.3)|
|CLBP4 - 9752235 - Culebra, PR||12 mi||125 min||86°F||84°F||1017 hPa|
|YABP4 - 9754228 - Yabucoa Harbor, PR||22 mi||125 min||88°F|
|LAMV3||39 mi||125 min||84°F||84°F|
|SJNP4 - 9755371 - San Juan, PR||42 mi||131 min||83°F||1016.7 hPa|
|41053 - San Juan, PR||42 mi||143 min||E 16 G 19||83°F||83°F||4 ft||1015.8 hPa (+0.9)|
|JOXP4 - Jobos Bay Reserve, Puerto Rico||44 mi||158 min||E 9.9||86°F||1017 hPa||73°F|
Wind History for Isabel Segunda, Vieques Island, 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||36 mi||87 min||E 16||9.00 mi||A Few Clouds||86°F||75°F||72%||1016.2 hPa|
Wind History from JSJ (wind in knots)
|1 day ago||E||E||E||E|
|2 days ago||E||E||E||E||SE||E||E||E||E||E||E||SE||SE||Calm||Calm||E||Calm||SE||SE||SE||E||E||E|
EDIT RT Ports Option Weekend mode (on/off) (on/off)  Help One Week of Data
|Punta Mulas |
Click for Map
Fri -- 02:29 AM AST 0.20 feet Low Tide
Fri -- 06:16 AM AST Sunrise
Fri -- 06:53 AM AST Moonrise
Fri -- 09:14 AM AST 1.32 feet High Tide
Fri -- 03:37 PM AST 0.37 feet Low Tide
Fri -- 05:55 PM AST Sunset
Fri -- 06:49 PM AST Moonset
Fri -- 09:06 PM AST 0.94 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
EDIT (on/off)  Help One Week of Data
|Vieques Passage |
Click for Map
Fri -- 02:09 AM AST -0.00 knots Slack
Fri -- 05:07 AM AST -0.56 knots Max Ebb
Fri -- 06:17 AM AST Sunrise
Fri -- 06:54 AM AST Moonrise
Fri -- 07:56 AM AST 0.00 knots Slack
Fri -- 11:16 AM AST 0.75 knots Max Flood
Fri -- 02:26 PM AST -0.00 knots Slack
Fri -- 05:50 PM AST -0.83 knots Max Ebb
Fri -- 05:56 PM AST Sunset
Fri -- 06:50 PM AST Moonset
Fri -- 09:25 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 (12,3,4,5)(on/off)  Help
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