Winter Storm Warning 5, NWS Juneau, AK

636 
WWAK47 PAJK 240851
WSWAJK

URGENT - WINTER WEATHER MESSAGE
National Weather Service Juneau AK
1151 PM AKST Sat Jan 23 2021


AKZ025-241000-
/O.EXP.PAJK.WS.W.0005.000000T0000Z-210124T0900Z/
Juneau Borough and Northern Admiralty Island-
Including the city of Juneau
1151 PM AKST Sat Jan 23 2021

...WINTER STORM WARNING WILL EXPIRE AT MIDNIGHT AKST TONIGHT...

Snow has diminished across the area with some light snow showers
expected for the rest of the night. Snow totals ranged from 4 to 6
inches with the highest amounts in the Mendenhall Valley.

$$

AKZ026-028-241400-
/O.CON.PAJK.WW.Y.0006.000000T0000Z-210124T1400Z/
Inner Channels from Kupreanof Island to Etolin Island-
Southern Inner Channels-
Including the cities of Petersburg, Wrangell, Kake, Ketchikan, 
and Metlakatla
1151 PM AKST Sat Jan 23 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 AM AKST
SUNDAY...

* WHAT...Wet snow. Additional snow accumulations of 1 to 3 
  inches for a storm total of 3 to 5 inches.

* WHERE...Inner Channels from Kupreanof Island to Etolin Island 
  and the Southern Inner Channels, including the cities of 
  Petersburg, Wrangell, and Ketchikan.

* WHEN...Until 5 AM AKST Sunday.

* IMPACTS...Wet, compact snow will stick to trees an may cause 
  power outages.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

&&

$$

http://www.weather.gov/juneau

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
316 PM AKST Sat Jan 23 2021

.SHORT TERM.../Through Sunday night/...A weak weather front (by
Alaskan Winter standards) is pushing its way across the panhandle
as of this afternoon and snow has been falling for most of the day
for more northerly locations. Snow started after noon in the
Ketchikan area and has yet to start in Hyder. Snow will transition
to showers early on, with snow showers tapering off on Sunday,
then ending by late Sunday night. Previous few forecasts have been
advertising sub-advisory snow totals and this forecast remains
consistent with that thought; 24 snow totals of 4 inches or less.
The front itself is sharply defined, both in model data and in
satellite imagery. Over the eastern Gulf, an abrupt wind will be
observed from small craft southeasterlies to small craft
westerlies this evening. Terrain will make the wind shift
associated with frontal passage much less pronounced over land and
the inner channels, but will still be readily observed as the
barometer begins to rise. Satellite imagery shows a clean break
between the colder, higher pre-frontal stratiform clouds and the
convective clouds on the back side of the front.

Small craft conditions limited to the eastern Gulf, Yakutat Bay,
and Cross Sound for combinations of winds, high seas, or both.

Updates today drew upon the GFS for PoP and QPF. Winds a blend of
GFS, NAM, and the Canadian NH for Sunday onward. Temps adjusted
using the National Blend of Models. Overall forecast confidence is
average for snow totals and trending above average for other
forecast elements.

.LONG TERM.../Monday through Friday/ As of 10pm Friday. Majority
of the extended forecast consists of high pressure building over
the Yukon predominately northerly outflow winds through the
inside waters. A low is progged to pass through the central gulf
Monday night, then looks to get shunted off to SE into Tuesday
morning. Latest models are more offshore with this system, so have
lowered POP to a chance/slight chance along the outer coast. As
the low moves south of the area, an inverted trough remains over
the inside waters. This, along with the building high pressure,
will cause a tightening pressure gradient along the Coast
Mountains. This is a dry pattern for SE Alaska, so have reduced
the POP forecast through the rest of the week.

The north wind looks to bring with it CAA. 850mb temps gradually
cool to around -20C along the northern border by Wednesday
morning and to around -10C over the south Wed night. This cold
air will help to drive the wind through interior passes. Have
increased speeds in N. Lynn Canal to 30kt on Tues and Wed, but if
model trends continue, may need to be increased to Gale force
35kt. The cold air and wind brings potential for freezing spray to
the forecast for the first time this year as well.

Another gulf low approaches towards the end of the week, but
latest models have delayed it until early Friday, then have it
shifting away to the SE again. This often happens with the
outflow winning out or being "blocked" at the upper levels from
making progress through an upper level ridge. For this reason,
have again kept POP below most guidance and continued with the
trend of cooling temperatures. Expect this to be the 1st real
"cold air outbreak" of the season and could easily last for the
standard 10 days or more.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Gale Warning for PKZ052.
     Small Craft Advisory for PKZ022-041>043-051-053.

&&

Fritsch/Ferrin

Visit us at http://www.weather.gov/Juneau

Special Weather Statement
National Weather Service Juneau AK
507 PM AKST Sat Jan 23 2021

AKZ018>021-024>028-241500-
Taiya Inlet and Klondike Highway-Haines Borough and Lynn Canal-
Glacier Bay-Eastern Chichagof Island-
Eastern Baranof Island and Southern Admiralty Island-
Juneau Borough and Northern Admiralty Island-
Inner Channels from Kupreanof Island to Etolin Island-
Dixon Entrance to Cape Decision Coastal Area-
Southern Inner Channels-
Including the cities of Skagway, Haines, Gustavus, Hoonah,
Angoon, Juneau, Petersburg, Wrangell, Kake, Craig, Klawock,
Ketchikan, and Metlakatla
507 PM AKST Sat Jan 23 2021

...ACCUMULATING SNOW THROUGH SUNDAY MORNING...

Dense, wet snow will continue to fall across the region with minor
accumulations at sea level. 24 hour total snowfall amounts
through Sunday morning will range from 1 to 5 inches.

Juneau, 2 to 5 inches.
Haines and Skagway, 1 to 3 inches.
Gustavus, 1 to 4 inches.
Hoonah, 1 to 2 inches.
Petersburg and Wrangell, 1 to 5 inches.
Elfin Cove and Pelican, 1 to 2 inches.
Prince of Wales and Ketchikan, around 1 inch.