Sunday, August20, 2017 L-36.com


Marine Weather and Tides
Happy Valley, AK

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 6:19AMSunset 9:45PM Saturday August 19, 2017 8:11 PM AKDT (04:11 UTC) Moonrise 1:46AMMoonset 6:53PM Illumination 5% Phase: Waning Crescent; Moon at 27 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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PKZ140 Cook Inlet North Of Kalgin Island- 351 Pm Akdt Sat Aug 19 2017
Tonight..Variable wind less than 10 kt. Seas 2 ft.
Sun..NE wind 10 kt increasing to 15 kt in the afternoon. Seas 2 ft building to 4 ft in the afternoon. Rain.
Sun night..N wind 20 kt. Seas 5 ft. Rain.
Mon..NE wind 15 kt. Seas 4 ft.
Mon night..N wind 10 kt. Seas 2 ft.
Tue through Wed..S wind 10 kt. Seas 2 ft.
Thu..NE wind 10 kt. Seas 2 ft.

7 Day Forecast for Marine Location Near Happy Valley, AK
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location: 60.02, -151.72     debug


Area Discussion for -
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Fxak68 pafc 191237
afdafc
southcentral and southwest alaska forecast discussion
national weather service anchorage ak
437 am akdt Sat aug 19 2017

Analysis and upper levels
For the fourth day in a row, a shortwave associated with a jet
streak is enhancing the western periphery of the arctic trough
that is currently entrenched across the alaska mainland. Within
this arctic trough is a rather potent closed low which continues
to advect colder air across most of alaska. This "bowling ball
low" has been tracking across the bering sea coast with showers
evident on the nome nexrad. Subsidence out ahead of the low has
brought a brief reprieve of showers to southwest alaska but with a
very moist stable layer coupled with a slightly stable
environment, fog has been steadily developing overnight.

Southcentral alaska on the other hand remains quite showery as a
strong shortwave on the southern end of the arctic trough
continues to move across the region. The same subsidence over
southwest alaska has begun to move over southcentral alaska which
should help reduce shower activity and coverage throughout the
day.

An area of low pressure associated with ex-tropical storm banyan
currently located south of atka looks to be weakening with a lot
of the upper level support shifting further east. However, recent
water vapor and infrared satellite imagery shows weak cyclonic
rotation developing along a frontal boundary associated with the
aforementioned low pressure system. While there is little sensible
weather associated with this system as it is well south of the
aleutian chain, that will change over the weekend as the developing
low quickly pushes into the gulf of alaska.

Model discussion
Numerical guidance is in remarkable agreement once again this
morning. It's been surprising just how well the models have been
progging the individual jet streaks that continue to enhance the
arctic trough that has been over alaska for over a week now. Since
the models initialized these features well, overall confidence
for the forecast package remains higher than normal. The only real
discrepancy of note is how the triple point low develops south of
cold bay over the next 18 to 24 hours. Model spread on low
placement is initially pretty large as they try to resolve the
development of the low but are in pretty good agreement with it
entering the western gulf Sunday morning. It looks like the most
recent model runs keep the low further west and south than the
runs last night which keeps interior portions of southcentral
alaska drier than previous runs. Basically, confidence is lower on
how much rainfall areas like anchorage and palmer will receive
while the entire northern gulf coast will see plenty of rainfall
on Sunday.

Aviation
Panc...VFR conditions are expected through the forecast period
with some showers developing toward Sunday morning.

Short term forecast southcentral alaska (days 1 and 2)
The upper level trough over southcentral alaska this morning will
drift northeast today and exit the area this afternoon, resulting
in a decrease in shower activity today. The upper level low
centered over the seward peninsula will move south for the next
couple of days, entering the gulf just west of kodiak island
Sunday night. On Saturday night a system south of the alaska
peninsula will get caught up in the flow of the upper low, and
will swing north into the gulf on Sunday. This will become a
fairly strong system on Sunday as it swings north into the
northwest gulf. Moisture with this system will push into the
southcentral mainland on Sunday and Sunday night, bringing another
round of rain to the area.

Short term forecast southwest alaska (days 1 and 2)
Expecting a fetch of moisture which is currently over the bering
to get entrained into the back side of the midlevel low bringing
precipitation into the ak peninsula tonight. A broad vortex over
western ak will continue to amplify enabling cooler air aloft to
work its way deeper into southwest alaska. Unsettled weather will
persist for the next few days as cooler air associated with the
trough moves southward. Between the embedded shortwaves and the
diurnal heating at the surface, the dynamics will be present to
support showers. Temperatures will hover near or slightly below
average for this time of year.

Short term forecast bering sea aleutians (days 1 and 2)
South of kiska, there is a closed low that is progged to move
eastward and slowly deepen. In its wake, expect ridging which
will keep a stable and relatively warm air mass in place. The
aleutian chain and portions of the bering can anticipate more fog
and stratus. The ridge axis will persist into next week keeping
the areas of pesky fog in place.

Long term forecast (days 4 through 7)
Beginning the extended period forecast Monday night, there will be
a closed upper low over the north gulf of alaska with a shortwave
ridge axis over the eastern bering sea. Expect showery and mostly
cloudy cool conditions to be over southcentral with drier weather
over southwest. Tuesday and Wednesday will be a transition period
as southern alaska moves into weak shortwave ridging as the upper
low weakens and moves east. Another trough over the bering sea
will move toward southwest alaska on Wednesday and eventually dig
south toward kodiak island through the remainder of the week. This
will keep a wet pattern in place across coastal regions with
clouds and rain chances for inland areas. The degree of downslope
flow for interior locations remains somewhat uncertain at this
point as the low track and placement will modulate that factor,
but it still looks wetter and cooler for most of interior southern
alaska for the foreseeable future.

Afc watches warnings advisories
Public... None.

Marine... None.

Fire weather... None.

Synopsis and model discussion... Mmc
southcentral alaska... Bl
southwest alaska bering sea aleutians... Jw
long term... Ja


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
46108 - Central Cook Inlet - 175 30 mi34 min 52°F1 ft
HMRA2 - Kachemak Bay Reserve, AK 33 mi42 min WNW 7 55°F 1006 hPa51°F
OVIA2 - 9455500 - Seldovia, AK 40 mi42 min 51°F
DRFA2 - Drift River Terminal, AK 43 mi42 min S 8 G 8.9 54°F 1007.2 hPa50°F
NKTA2 - 9455760 - Nikiski, AK 49 mi42 min W 4.1 G 5.1 55°F 56°F1007 hPa

Wind History for Nikiski, AK
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Homer, Homer Airport, AK29 mi19 minW 610.00 miMostly Cloudy57°F44°F62%1007.1 hPa

Wind History from AHO (wind in knots)
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Last 24hrN3CalmCalmCalmCalmN5CalmNE3N3CalmCalmCalmCalmSE4SE5SW5W4SW4SW6SW5S7SW6SW6W6
1 day agoW5CalmCalmCalmCalmCalmCalmCalmNE5NE3NE4NE3NE4NE4E6NE43S5SW8S7S6SW7W5NE3
2 days agoS7S4S5CalmCalmNE3CalmNE3NE3NE4NE3CalmE4E4NE5E4S3W6W7W6W7W8SW4W6

Tide / Current Tables for Cape Ninilchik, Cook Inlet, Alaska
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Cape Ninilchik
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Sun -- 02:22 AM AKDT     21.16 feet High Tide
Sun -- 05:05 AM AKDT     Moonrise
Sun -- 06:34 AM AKDT     Sunrise
Sun -- 09:05 AM AKDT     -2.73 feet Low Tide
Sun -- 03:20 PM AKDT     20.46 feet High Tide
Sun -- 09:18 PM AKDT     1.21 feet Low Tide
Sun -- 09:24 PM AKDT     Moonset
Sun -- 09:44 PM AKDT     Sunset
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
14.618.72120.718.3148.53-1.1-2.7-1.52.37.713.41820.319.917.312.97.73.51.325.2

Tide / Current Tables for Anchor Point, Kenai Peninsula, Alaska
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Anchor Point
Click for Map
Sun -- 02:10 AM AKDT     20.36 feet High Tide
Sun -- 05:07 AM AKDT     Moonrise
Sun -- 06:36 AM AKDT     Sunrise
Sun -- 08:32 AM AKDT     -2.93 feet Low Tide
Sun -- 03:08 PM AKDT     19.66 feet High Tide
Sun -- 08:45 PM AKDT     1.01 feet Low Tide
Sun -- 09:23 PM AKDT     Moonset
Sun -- 09:43 PM AKDT     Sunset
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
15.518.820.319.516.511.55.70.5-2.5-2.7-0.349.314.418.119.618.715.410.45.31.81.136.8

Weather Map and Satellite Images
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Weather Map
wmap_P
IR Satellite Image from GEOS
npac_satellite

GOES Local Image of Alaska    EDIT
Geos

Ground Weather Radar Station Kenai, AK
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weather_mapweather_map weather_map

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Disclaimer:
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.