High Wind in Alaska, March 10 to 12, 2023

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
236 PM AKST Thu Mar 9 2023

.SHORT TERM...Relatively clear and cold weather will continue
Friday for the panhandle as outflow continues, intensifying
through the day tomorrow as high pressure builds again in the
Yukon. Strong winds are expected tonight in areas such as downtown
Juneau and Skagway ahead of overall stronger winds once again
building in the inner channels. Gales are also expected to build
in the coastal waters Friday as the outflow winds ramp up Friday.
A small moisture deprived trough will continue to slide southward
just off of the SE gulf coast Friday morning, potentially bringing
some thin cloud cover and flurries as it passes.

As the days get longer heading into Spring many parts of the
panhandle continue to see increasing diurnal trends in temperature.
Most areas saw slightly higher maximum temperatures this
afternoon but are still expected to drop significantly overnight
again, especially in the inner channels sheltered from outflow
winds and continued minimal to no cloud cover. With minimal
features to track and no significant changes made, forecaster
confidence is above average for this time period.

.LONG TERM.../Saturday through Thursday/...Cold and breezy
weather will transition by next week with decreasing outflow
winds, an increase in temperatures, and higher chances for snow
and rain. The AK Gulf high pressure ridge shifted west as an upper
low dropped from the Yukon into the SE AK Gulf by Saturday.
Sunday night into Monday we begin the pattern shift as first mid
level trough drops southward from the AK interior into the AK
Gulf. This is followed by a broader trough which should become a
closed upper levels low centered more over the Western Gulf
Wednesday into Thursday. Beyond that time frame high uncertainty
on synoptic pattern.

Still keeping an eye for Taku wind event into Saturday but flow
should be more northerly v northeasterly, inversion is not very
strong, and not much of a critical level. Some chance for precip
hitting the southern areas as a surface low develops over Haida
Gwaii, most likely snow or a snow-rain mix, but accumulations
expected to be very light. As the upper level trough moves in
surface lows will start to track over the gulf in from the west. For
the start of the week the first in the series will be more to the
west, keeping the Panhandle dry but still cold with northerly winds.
Tuesday night into Wednesday the next low and associated front
positions over the NE Gulf as the front starts to cross over the
Panhandle. Due to cold air in place and low 850 mb temps watching
for accumulating snow. Right now models have the NE Gulf coast
getting highest QPF amounts and thus higher snow accumulation than
the rest of the region. Still bit early to nail down amounts but at
least a few inches for most locations. Southern areas get the warm
up sooner so will see more of a snow-rain mix. Used a blend of NAM
initially then GFS/ECMWF blend for the start of the week.

&&

.AVIATION...The biggest aviation hazard for Southeast Alaska
Thursday night and into Friday. Gusty winds have persisted in the
Skagway area through the day, and outflow winds are expected to
increase over the Icy Strait Corridor east to Juneau and
northward. Winds Friday out of the Stikine River Valley will
become gusty. Turbulence near rough terrain and ridges/hills with
some areas of Low-Level wind shear are possible, I think mainly
for the larger airports of Skagway, Haines, and Juneau, with
smaller ones of Hoonah, Elfin Cove, Pelican, and Gustavus airport
may also see similar issues.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Strong Wind from Friday morning through Friday afternoon for
     AKZ318.
     Gale Warning from 6 AM to 6 PM AKST Friday for AKZ322.
     Strong Wind from 9 PM AKST this evening through Friday afternoon
     for AKZ325.
MARINE...Gale Warning for PKZ012-013-643-644-651-663-664-671.
     Small Craft Advisory for PKZ011-022-031-053-642-652-661-662-672.

&&

SHORT TERM...STJ
LONG TERM....PRB
AVIATION...Bezenek

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