Gale Warning 277, NWS Juneau, AK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
911 AM AKST Sat Dec 2 2017

.UPDATE...We have expanded the coverage of the winter weather
advisory for freezing rain into the Hoonah, Angoon, and Tenakee
Springs area through noon today. Some unknown precipitation
showing up in the Angoon automated observation combined with sub-
freezing temperatures in the morning indicates the threat area is
larger. There may be a slight possibility in areas around this
identified core region, such as Haines/Skagway, Pelican/Elfin
Cove, and Sitka/Kake, but we think temperatures will either warm
much earlier, or the atmospheric column will overall be cooler and
precipitation will fall as snow.

&&

.PREV DISCUSSION......ISSUED AT ...648 AM AKST Saturday

UPDATE...Freezing rain began in the Juneau area and extends west
to near Gustavus. We are expecting the situation to last until
around noon today, so have issued a winter weather advisory for
the minor ice accumulations. Travel may become hazards due to
slippery surfaces. Light snow spreading in from west, should end
the freezing precipitation.

SHORT TERM.../ Saturday to Monday / Surface ridge over the
eastern gulf moves east in advance of the strong weather system
spreading in from the west. Just ahead of the strong system is a
weaker trough moving across the northern gulf and panhandle.
Expect this to spread some light snow and or rain to the area.
Right now temperatures are cool enough for the precipitation to
start as snow, though minor warming will be moving in from the south
that most regions will start changing to rain, except for the far
northern Lynn Canal should stay snow through Saturday night.

Sunday the lower 960's mb surface low will be south of Kodiak
Island and the front will be spreading across the gulf towards the
panhandle. 35 to 45 kt winds will lead the way with the warming
which will bring freezing levels to near 4000 ft over the gulf.
As the warm air works way into panhandle Sunday night, do not
think it will stay that high but should be roughly 2500 ft or so.
Outer coastal areas should see rain along with much of of the
inner channels by late afternoon. Northern Lynn Canal should mix
by Monday morning as well.

Gusty winds will also be impacting the outer coastal areas Sunday
night to Monday, and including a large section of the inner
channels on Monday while the front moves through.

LONG TERM.../Monday through Saturday as of 9 PM Friday/ Monday
begins with a weather front moving east over the Panhandle. Due to
the seasonably warm temperatures, all low elevation precipitation
associated with this front is expected to be rain. Precipitation
along the Haines and Klondike Highways may be a mix of rain and
snow and entirely snow closer to the border. Behind the front shower
activity diminishes through Monday evening.

Tuesday a low pressure system and its associated weather front
will track north across the Gulf. This will bring another round of
precipitation into the Panhandle on Tuesday; however, the track of
the front remains uncertain. Behind this front a southerly flow
pattern will set up which will continue the seasonably warm
temperatures through late in the week.

Little to no changes made in the extended forecast due to large
model discrepancies. WPC continues to favor an ensemble approach
through the extended forecast. The GFS favors a more westerly
approach for the low pressure system and its front on Tuesday
keeping precipitation more confined to the northern Panhandle and
allowing a brief dry out behind the Sunday and Monday system. The
ECMWF on the other hand is favoring a much more easterly track for
the system bringing the warm front into the southern Panhandle by
early Tuesday morning.

MARINE...A front with band of gale force winds head of it,
including a small barrier jet pocket of Storm force winds near
Cape Suckling Sunday afternoon will impact the marine waters until
the front moves inland Southeast Alaska by Monday. A building
swell behind the main front will increase the seas over the gulf
into the mid teens Sunday night and keep them there to Tuesday,
while it will top in the 20 to 24 foot range over the northern
gulf waters.

.AJK Watches/Warnings/Advisories...
PUBLIC...Winter Weather Advisory until noon AKST today for AKZ020-021-024-
     025.
MARINE...Small Craft Advisory for PKZ052.
     Small Craft Advisory due to Seas for PKZ022-041>043.

&&

Bezenek/Byrd

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

Special Weather Statement
National Weather Service Juneau AK
1044 AM AKST Sat Dec 2 2017

AKZ023-041945-
Cape Decision to Salisbury Sound Coastal Area-
Including the cities of Sitka and Port Alexander
1044 AM AKST Sat Dec 2 2017

...HIGH ASTRONOMICAL TIDES THROUGH TUESDAY FOR PORT ALEXANDER...

Each mid-day high tide this coming week will be higher than
normal. For the city of Port Alexander predicted tides will be
near the moderate flood stage of 14.2 feet each day. At this
level there can be flooding of the telephone building on the point
and gravel caused by waves onto the electric generator building.
The highest tide of the week will be on Monday at 1241 PM in Port
Alexander.

A front will cause winds to increase out of the S-SE Sunday night
into early Monday morning with winds of around 20 mph gusting to
40 mph. This will coincide with the high tide at 110 AM, but that
tide is predicted to be well below flood stage.

FERRIN