Friday, January19, 2018 L-36.com


Marine Weather and Tides
Kupreanof, 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 8:22AMSunset 3:55PM Friday January 19, 2018 2:34 AM AKST (11:34 UTC) Moonrise 10:26AMMoonset 8:06PM Illumination 7% Phase: Waxing Crescent; Moon at 3 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
    EDIT      (on/off)   Help
PKZ035 Sumner Strait- 341 Pm Akst Thu Jan 18 2018
Tonight..N wind 10 kt. Out of interior passes, gusts to 30 kt in the evening. Seas 2 ft, except 6 ft near ocean entrances.
Fri..N wind 15 kt. Seas 3 ft.
Fri night..NE wind 10 kt. Seas 2 ft.
Sat..NE wind 20 kt. Gusts to 35 kt. Seas 4 ft.
Sat night..NE wind 25 kt. Gusts to 40 kt, except 35 kt out of interior passes. Seas 5 ft.
Sun..E wind 20 kt. Seas 4 ft.
Mon..SE wind 15 kt. Seas 3 ft.
Tue..SE wind 10 kt. Seas 2 ft or less.

7 Day Forecast for Marine Location Near Kupreanof, AK
   Hourly   EDIT   Help
location: 56.65, -133.15     debug


Area Discussion for -
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
Fxak67 pajk 182314
afdajk
southeast alaska forecast discussion
national weather service juneau ak
214 pm akst Thu jan 18 2018

Short term Northerly gradients across southeast alaska is
showing signs of easing as the low well to our south, in fact,
south of haida gwaii is now weakening. However, to allow slower
easing of winds, the low is forecast to approach southeast via
hecate strait through Saturday and eventually die an uneventful
death. Bands of showers that have moved north through the day
across our central region have steadily weakened and have merely
resulted in thickened clouds across much of the north-central
panhandle. Thus, juneau and points north will remain dry. Showers
will end across the south-central panhandle tonight including
sitka, wrangell, and petersburg. But ketchikan will continue with
rain chances through Friday.

As the weakening low progresses northward into Friday night, we
expand rain chances yet again across the south. And northerlies
through lynn canal and some other north-south channels will begin
to rebuild from a lighter period on Friday.

Saturday, a new more vigorous system will move into the outer
central gulf and spawn a wave in the southeast gulf that will
quickly kill off the previous feature described above. This system
may induce some breezy conditions for the far south including
hydaburg and craig and probably will spread showers farther north
up the coast into the elfin cove area including sitka, petersburg,
and wrangell. Due to some weak cold air advection, we do
anticipate that much of the shower activity though weak will
support snow across much of the interior and northern
locations. As the system glides northwest across the panhandle,
we foresee the chance of more breezy conditions developing across
downtown juneau Saturday night. In addition, the tighter northerly
pressure gradient across southeast will result in stronger winds
with small crafts likely in lynn canal, stephens, and sumner at
some point Saturday.

We preferred the gfs ECMWF solutions consensus with the lows'
tracks through the period. Forecast confidence is generally good.

Details, such as the proper strength of some of these wind set-ups
will emerge later.

Long term Saturday through Thursday... We'll be heading into a
relatively active, but tricky, pattern for the alaskan panhandle
in the long term. Potential temperature analysis currently
indicates the development of an omega block, with the upper level
ridge axis centered over the bering sea, which will influence our
weather during this period. The broad upper level trough
associated with this blocking pattern will largely develop over
mainland alaska and extend south into the gulf of alaska. This
will leave all of mainland alaska and the SE panhandle as the
prime target for a much colder, arctic air mass to move in aloft.

Model 850 mb temperature analysis continues to show falling
temperatures into the weekend, with the mainland receiving the
heavier dose of arctic-like temperatures. We've left surface
temperatures in the forecast average to below average accordingly
for this time of year, meaning temperatures should start to feel
like winter again for SE alaska.

Embedded shortwaves within the larger trough, and their associated
surface lows, will largely remain offshore of the panhandle in
the east-southeast gulf. A subsequent ridge will build over
western canada, being squeezed by the stronger trough over the
gulf. This should provide a brief moment through the weekend of
offshore flow, implying drier conditions, especially for portions
of the northern panhandle. Due to the uncertainty regarding the
exact position of the lows, the southern panhandle may not remain
as dry, so we've left slightly higher chances of precipitation
there through the weekend. By the early part of next week, models
indicate that the broad upper level trough will begin to break
down, allowing the shortwaves to track more northeastward towards
the panhandle. This should gradually increase pops throughout the
panhandle going into the middle of next week.

Generally, a lot of uncertainty exists with this forecast. Models
agree on upper level features, at least into the early part of next
week before disagreement ensues. However, there is quite a bit of
model spread regarding surface features, which will have an
impact on precipitation chances. The cold air mass will largely
remain entrenched, so any precipitation that does fall, would most
likely fall as snow. Due to outflow conditions through the
weekend, we anticipate most of the northern inner channel winds to
remain around 20 kt or higher, as a strong pressure gradient and
temperature gradient will provide brisk northerly flow throughout
the inside waters.

We elected to use a gfs ECMWF model blend for the earlier portion
of the long term (12z Sat through 12z sun) and decided to remain
with wpc guidance past this timeframe due to the model spread and
uncertainty.

Ajk watches warnings advisories
Public... None.

Marine... Small craft advisory for pkz012-041.

Small craft advisory due to seas for pkz042-043-051-052.

Jwa voveris
visit us at http:

Weather Reporting Stations
   EDIT       (on/off)   Help   NOTE: Click on distance to see the station location on a map
Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
LCNA2 - Lincoln Rock, AK 48 mi84 min ESE 2.9 G 4.1 39°F 998.5 hPa39°F
FFIA2 - Five Finger, AK 50 mi34 min E 1 G 1.9 38°F 1000.3 hPa (+1.3)

Wind History for Port Alexander, AK
(wind in knots)    EDIT      (on/off)   Help
3
AM
4
AM
5
AM
6
AM
7
AM
8
AM
9
AM
10
AM
11
AM
12
PM
1
PM
2
PM
3
PM
4
PM
5
PM
6
PM
7
PM
8
PM
9
PM
10
PM
11
PM
12
AM
1
AM
2
AM
Last
24hr
N10
G19
N9
G20
N11
G17
N11
G15
N9
G13
N9
G16
N10
G18
N11
G17
N9
G17
N12
G16
N13
N10
G16
N6
G13
N11
G20
N6
G13
N7
G13
N8
G14
N7
G11
N5
G11
N5
G10
N7
G11
N5
G9
N5
G9
N4
1 day
ago
--
NW2
--
N2
N2
G6
N6
G9
N8
G12
N7
G13
N8
G18
N13
G19
N11
G16
N10
G20
N14
G19
N9
G17
N8
G17
N11
G15
N7
G14
N5
G11
N9
G15
N11
G16
N12
G20
N12
G18
N13
G20
N14
G21
2 days
ago
--
--
NE1
G5
--
SE1
--
--
SE1
G4
S5
G13
SE1
--
--
--
--
--
--
--
NE1
E1
--
--
NW1
G5

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Petersburg, AK16 mi38 minN 06.00 miFog/Mist36°F36°F100%1001.5 hPa

Wind History from APG (wind in knots)
3
AM
4
AM
5
AM
6
AM
7
AM
8
AM
9
AM
10
AM
11
AM
12
PM
1
PM
2
PM
3
PM
4
PM
5
PM
6
PM
7
PM
8
PM
9
PM
10
PM
11
PM
12
AM
1
AM
2
AM
Last 24hrSE3E3CalmCalmCalmCalmCalmCalmE3E3E3E3SE5E3CalmCalmCalmCalmCalmE3CalmSE3CalmCalm
1 day agoCalmCalmE4SW4SE3CalmSW4E3CalmCalmE3E3CalmCalmCalmCalmSW5CalmCalmCalmCalmCalmCalmE3
2 days ago3W63NW6S13
G23
SE7SE7SE9
G15
SE11
G18
S7
G18
S10
G18
5SW53Calm4S3S9
G16
5W3CalmE7Calm4

Tide / Current Tables for Castle Islands, Duncan Canal, Alaska
   EDIT   RT Ports Option   Weekend mode (on/off)   (on/off)   Help   One Week of Data
Castle Islands
Click for Map
Fri -- 02:40 AM AKST     14.92 feet High Tide
Fri -- 08:03 AM AKST     3.16 feet Low Tide
Fri -- 08:11 AM AKST     Sunrise
Fri -- 09:25 AM AKST     Moonrise
Fri -- 02:17 PM AKST     16.20 feet High Tide
Fri -- 03:55 PM AKST     Sunset
Fri -- 07:06 PM AKST     Moonset
Fri -- 08:27 PM AKST     -0.87 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
9.612.714.514.813.310.36.94.23.23.96.19.212.314.916.115.713.39.45.11.4-0.6-0.61.24.3

Tide / Current Tables for Grief Island, Duncan Canal, Alaska
   EDIT      (on/off)   Help   One Week of Data
Grief Island
Click for Map
Fri -- 02:27 AM AKST     15.00 feet High Tide
Fri -- 08:01 AM AKST     3.27 feet Low Tide
Fri -- 08:11 AM AKST     Sunrise
Fri -- 09:25 AM AKST     Moonrise
Fri -- 02:04 PM AKST     16.31 feet High Tide
Fri -- 03:55 PM AKST     Sunset
Fri -- 07:06 PM AKST     Moonset
Fri -- 08:26 PM AKST     -0.84 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
10.113.214.814.712.99.96.74.23.34.16.49.612.815.316.315.512.994.71.3-0.6-0.51.44.6

Weather Map and Satellite Images
       (on/off)   Help
Weather Map
wmap_P
IR Satellite Image from GEOS
west_satellite

GOES Local Image of PacificNorthwest    EDIT
Geos

Wind Forecast for (6,6,7,8)
      (on/off)   Help

Ground Weather Radar Station Biorka Is., AK
   (on/off)   Help
weather_mapweather_map weather_map

Ad by Google

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.