Thursday, August17, 2017

Marine Weather and Tides
Arroyo, PR

Version 3.4
What's New / NOTES
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 5:29AMSunset 5:59PM Thursday August 17, 2017 6:58 PM CST (00:58 UTC) Moonrise 3:41AMMoonset 2:13PM Illumination 19% Phase: Waning Crescent; Moon at 25 days in cycle
NOTE: Some of the data on this page has not been verified and should be used with that in mind. It may and occasionally will, be wrong. The tide reports are by xtide and are NOT FOR NAVIGATION.
Marine Forecasts
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7 Day Forecast for Marine Location Near Arroyo, PR
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location: -34.81, -58.22     debug

Area Discussion for - San Juan, PR
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Fxca62 tjsj 171942
area forecast discussion
national weather service san juan pr
342 pm ast Thu aug 17 2017

Synopsis A very active tropical wave now moving across the forecast
area will continue to produce showers and thunderstorms across parts
of the islands and local waters during the rest of today and overnight.

A tutt low will shift farther west of the forecast area overnight,as
an upper ridge will gradually build from the north through Saturday.

An area of low pressure east of the lesser antilles is expected to move
across the eastern caribbean late Friday through Saturday. This will
increase the potential for squally conditions and thunderstorms mainly
across the caribbean waters. The national hurricane center is issuing
advisories on this potential tropical cyclone nine and an air force
reserve hurricane hunter aircraft is currently enroute to investigate
the disturbance.

Short term Overnight through Saturday... The combination of the
tropical wave passing through the local area and the proximity of
the upper trough west of the region will maintain unstable weather
conditions over the forecast area overnight through early Friday.

Showers and thunderstorms over the islands should diminish by early
evening, but is expected to again redevelop across the coastal waters
and reach portions of pr and the usvi by early morning. Somewhat drier
conditions is expected by Friday afternoon as the tropical wave will
have exited the region, and the upper level ridge gradually builds
over the area along with an intrusion of suspended saharan dust
expected to move across the region. On Saturday the chance for showers
and thunderstorms will again increase as invest 91l potential tropical
cyclone nine moves south of the area and peripheral moisture is expected
to propagate northward and affect the forecast area.

Long term Sunday through Friday... The area of low pressure invest
92l, currently has a 60 percent chance of formation through the next
5 days. Based on recent info from the national hurricane center, this
system is expected to encounter unfavorable upper level winds for further
development and should move northeast of the islands on Sunday as a
tropical wave. However, recent model guidance continued to suggest
that the overall layered precipitable water moisture content will
remain high through the early part of next week. This should support
showers and isolated thunderstorm development each day across the
islands. Another tropical wave and tutt low is forecast to approach
the local area by Tuesday. This should bring increased instability
and favorable conditions for enhanced convective development through
at least Wednesday. So far, a gradual improvement in the overall weather
pattern is expected across the region by Thursday and Friday.

Aviation Bkn-ovc skies expected through the afternoon across the
terminals in pr while the usvi and tncm tkpk observes mainly few_sct
clouds. CIGS across terminals in pr will be at fl080 to about fl110.

Wx improving this afternoon and tonight. Winds will remain mainly
easterly at 10-15kt with occasional higher gusts for the rest of
today, decreasing winds tonight. MainlyVFR conds expected starting
this afternoon into Friday, winds increasing after 18 13z at about
15kt from the east.

Marine Showers and isolated thunderstorms will affect parts of
the regional waters during the rest of the overnight hours, as the
tropical wave will continue to exit the region. Small craft advisories
will continue in effect across much of the local waters, due to winds
of up to 20 knots and seas up to 8 feet.

Moderate to high risk of rip currents across the local islands

Preliminary point temps pops
Sju 76 88 78 88 30 20 60 40
stt 75 92 80 89 20 20 50 50

Sju watches warnings advisories
Pr... High rip current risk until 6 pm ast this evening for central
interior-north central-northeast-northwest-san juan and
vicinity-southeast-western interior.

Vi... High rip current risk until 6 pm ast this evening for st croix.

Small craft advisory until 6 pm ast Saturday for st.Thomas... St.

John... And adjacent islands.

Am... High rip current risk until 6 pm ast this evening for coastal
waters of southern puerto rico out 10 nm.

Small craft advisory until 6 pm ast Saturday for anegada passage
southward to 17n-atlantic waters of puerto rico and usvi
from 10 nm to 19.5n-caribbean waters of puerto rico from 10
nm to 17n-coastal waters of southern usvi vieques and
eastern puerto rico out 10 nm.

Small craft advisory until 2 am ast Friday for coastal waters of
northern puerto rico out 10 nm.

Small craft advisory from 2 am to 6 pm ast Saturday for coastal
waters of northern puerto rico out 10 nm-coastal waters of
northern usvi and culebra out 10 nm-mona passage southward
to 17n.

Small craft advisory until 6 pm ast this evening for coastal
waters of northern usvi and culebra out 10 nm-mona passage
southward to 17n.

Short term... Jf
long term... .Ram

Weather Reporting Stations
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Airport Reports
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Tide / Current Tables for
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Weather Map and Satellite Images
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Weather Map
IR Satellite Image from GEOS

GOES Local Image of Puerto Rico    EDIT

Wind Forecast for (20,4,5,8)
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Ground Weather Radar Station Puerto Rico,Virgin Islands
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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 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 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.