Marine Weather and Tides
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.
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.
|Sunrise 6:04AM||Sunset 6:45PM||Friday April 20, 2018 2:29 PM AST (18:29 UTC)||Moonrise 10:04AM||Moonset 11:30PM||Illumination 29%|
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|AMZ735 Coastal Waters Of Southern Puerto Rico Out 10 Nm- 1036 Am Ast Fri Apr 20 2018 |
.small craft should exercise caution...
Rest of today..East winds 15 to 20 knots. Seas 4 to 6 feet with occasional seas up to 8 feet. Dominant period 12 seconds. Northeast swell 4 to 5 feet. Isolated showers through the day.
Tonight..East winds 15 to 20 knots. Seas 4 to 6 feet with occasional seas up to 8 feet. Dominant period 7 seconds. East swell 4 to 5 feet in the evening. 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 7 seconds. Isolated showers.
Saturday night..East winds 15 to 20 knots. Seas 2 to 4 feet with occasional seas up to 5 feet. Dominant period 7 seconds. Isolated showers.
Sunday..East winds 15 to 20 knots. Seas 3 to 5 feet with occasional seas up to 6 feet. Dominant period 7 seconds. Isolated showers.
Monday..East winds 10 to 15 knots. Seas 1 to 3 feet. Dominant period 7 seconds. Isolated showers.
Tuesday..East winds 10 to 15 knots. Seas 1 to 3 feet. Dominant period 7 seconds. Scattered showers.
|AMZ700 1036 Am Ast Fri Apr 20 2018 |
Synopsis for puerto rico and the uS. Virgin islands waters... A moderate to locally fresh wind flow will prevail across the regional waters through early the next week. A long dominant period northeast swell will continue to move across the local waters today. Seas will gradually subside through the weekend.
7 Day Forecast for Marine Location Near Playita Cortada, PRHourly EDIT Help
Area Discussion for - San Juan, PR  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxca62 tjsj 201436|
area forecast discussion
national weather service san juan pr
1036 am ast Fri apr 20 2018
Update Minor changes were introduced at this time to match
current conditions. The chance for shower and thunderstorms
development continues particularly for the northwest quadrant
of puerto rico.
Aviation Periods of MVFR conds likely aft 20 16z in and around
jmz jbq and possibly jsj in shra tsra. Ese winds around 10-15
knots with some sea breeze variations.
Marine Hazardous seas are expected across the offshore atlantic
and caribbean waters, anegada and mona passage due to a long
period northeasterly swell. Seas up to 8 feet throughout the day.
Prev discussion issued 505 am ast Fri apr 20 2018
synopsis... Broad surface high pressure will continue across the
eastern atlantic through early next week. Patches of moisture
embedded in the trades will move occasionally across the region
for the next several days, inducing the development of showers and
thunderstorms each afternoon across interior and western puerto
rico with isolated to scattered showers across the u.S. Virgin
islands and eastern puerto rico during the nights and early
Short term... Today through Sunday...
slightly drier air made its way into the local area last night,
causing a decrease in shower activity across the local islands.
However, an increase in moisture is expected today, which will
combine with the local effects and diurnal heating to cause showers
and isolated thunderstorms over puerto rico this afternoon. High
resolution model guidance suggests that with the exception of the
south coastal sections of pr, the rest of the island may observe
some rain with isolated sports of heavy rain across nw-pr and
portions of the interior and north central. For that reason only
minor modifications were made tot he inherited forecast and left
good probability of precip with isolated thunderstorms for the
forecast for this afternoon.
Scattered showers may affect the usvi but the western sections of st
thomas and st croix have a slightly higher chance of rain because
showers are expected to develop over the islands and stream off to
the west, so parts of those showers could affect the western
Another patch of moisture is expected tonight into Saturday, which
may cause scattered to locally numerous showers overnight tonight
across the local waters, usvi and eastern pr with isolated
thunderstorms once again in the afternoon hours over the interior
into nw-pr. There is also an upper trough that will be moving in
from the west which may increase instability over pr and cause
slightly more persistent thunderstorms. Bu Sunday, drier air has|
moved in and wind flow may shift a bit to the ene, which may cause
afternoon convection across sw-pr with isolated showers elsewhere.
Long term... Monday through Friday...
moisture peaks on Monday and Tuesday and an upper level trough
will support thunderstorm development each day. But overall the
same weather pattern is expected to prevail each day. Shower and
thunderstorm development is expected to develop each afternoon
over portions of western puerto rico. Trade wind showers will
persist across the usvi and eastern portions of pr during the
overnight and early morning hours. Drier air is expected to move
once again from the east by Friday. Day time maximum temperatures
are expected to reach the high 80s to low 90s across the lower
elevations and overnight minimum temperatures are expected to
range from the low 60s across the higher elevations to low 70s
along the lower elevations.
Aviation...VFR conds in the morning hours across the local
terminals. Shra shra expected this afternoon may cause moments of
MVFR across tjsj, tjmz, and tjbq after 20 16z. Tempo groups were
left out due to exact timing uncertainty except tjbq which may have
convection after 20 19z. Winds will be from the east becoming breezy
at 15-20kt and gusty.
Marine... A long period northeast swell will continue to result
in life threatening rip currents across the north, east and
southeast facing beaches of puerto rico, culebra, vieques and st.
Croix. Small craft advisories are in effect for the offshore
waters and passages due to seas up to 7 feet. East winds will
continue at 15 to 20 knots across the region through the weekend.
Preliminary point temps pops
Sju 88 75 86 75 40 40 40 20
stt 86 76 85 75 40 40 20 20
Sju watches warnings advisories
Pr... High rip current risk through late tonight for central interior-
culebra-north central-northeast-northwest-san juan and
Vi... High rip current risk through late Saturday night for st croix.
Am... High rip current risk through late tonight for coastal waters of
southern puerto rico out 10 nm.
Small craft advisory until 8 pm ast this evening for anegada
passage southward to 17n-caribbean waters of puerto rico
from 10 nm to 17n-mona passage southward to 17n.
Small craft advisory until 6 pm ast Saturday for atlantic waters
of puerto rico and usvi from 10 nm to 19.5n.
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|
|JOXP4 - Jobos Bay Reserve, Puerto Rico||12 mi||105 min||E 8.9||83°F||1019 hPa||73°F|
|MGIP4 - 9759110 - Magueyes Islands, PR||32 mi||42 min||SE 5.1 G 11||84°F||81°F||1017.3 hPa|
|YABP4 - 9754228 - Yabucoa Harbor, PR||33 mi||42 min||84°F|
|AROP4 - 9757809 - Arecibo, PR||37 mi||42 min||ENE 12 G 19|
|SJNP4 - 9755371 - San Juan, PR||38 mi||48 min||80°F||80°F||1017.6 hPa|
|41053 - San Juan, PR||39 mi||60 min||E 18 G 23||80°F||1017 hPa|
Wind History for Penuelas (Punta Guayanilla), PR(wind in knots) EDIT (on/off)  Help
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports
Wind History from JPS (wind in knots)
|1 day ago|
|2 days ago|
EDIT RT Ports Option Weekend mode (on/off) (on/off)  Help One Week of Data
|Playa Cortada |
Click for Map
Fri -- 02:18 AM AST 0.92 feet High Tide
Fri -- 06:05 AM AST Sunrise
Fri -- 10:03 AM AST Moonrise
Fri -- 02:26 PM AST -0.08 feet Low Tide
Fri -- 06:43 PM AST Sunset
Fri -- 11:29 PM AST Moonset
Tide / Current data from XTide NOT FOR NAVIGATION
EDIT (on/off)  Help One Week of Data
|Playa de Ponce |
Click for Map
Fri -- 01:24 AM AST 0.65 feet High Tide
Fri -- 06:06 AM AST Sunrise
Fri -- 10:04 AM AST Moonrise
Fri -- 02:38 PM AST -0.30 feet Low Tide
Fri -- 06:44 PM AST Sunset
Fri -- 11:29 PM AST Moonset
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.
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Other links: Northern Pacific Contential US Full GOES-East
Wind Forecast for (14,3,4,5)(on/off)  Help
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