High Wind in Alaska, March 31, 2024

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
258 PM AKDT Sat Mar 30 2024

.SHORT TERM...Similar ideas to yesterday's short term forecast and
long term forecast for day 3. The stronger front on Saturday
night comes from a strong parent low near Kodiak Island. As the
front begins to impact the panhandle with the low center around
the northern coast, a barrier jet looks to form along the NE gulf
coast. Moderate gales up to around 40 knots along the NE gulf
coast will be generated from the frontal band as it moves into the
panhandle. A plume of moisture, mostly aimed at the north gulf
coast, does extend into the Yakutat area. Trended down
precipitation slightly on the onset of the system. Finally, as the
upper level 500 mb jet moves into the Yukon, expect some surface
level troughing and winds in Lynn Canal and Skagway to increase to
up to 30 knots. Behind the front, a cold punch of gale force winds
in the gulf and copious amounts of CAA at the 850 mb level will
encourage some rain and snow showers. Expect these to be rather
sporadic in nature with little moisture available. No significant
accumulation is expected.

Some changes to the forecast include increasing winds in northern
Lynn Canal to low end gale force. The tightening gradient with
accompanying WAA look to create a mixed profile up to 700 mb,
promoting the upgrade to a gale. Expect this wind to be sustained
as long as westerly to southwesterly wind from 850-700 mb winds
remain sufficiently strong (>50 knots) for lee side troughing on
the eastern side of the mountains near Lynn Canal.

.LONG TERM...At the start of the long term, we will see a new low
rotating around the original low located near Anchorage. This low
will race northward and is expected to bring a reinforcing shot of
wind and precipitation to the panhandle. Places north of Sitka and
Angoon are expected to stay as a mix of rain and snow or just snow
depending on location and elevation. South of these locations,
precipitation should stay as rain or a mix of rain and snow for
Monday into Tuesday. After this system moves through the area,
onshore flow is expected to continue bringing unsettled weather to
the panhandle. Rain and snow showers will remain possible Tuesday
before we start to dry out Tuesday evening to Wednesday morning
from north to south. Towards the end of the week, the chance of
precipitation starts to increase again but confidence remains
lower so possibility of seeing precip stayed lowered.

Temperatures during this time will continue to remain cooler,
especially during the overnight hours. The best chance of cooler
temperatures comes as we start to dry out
Tuesday and into Wednesday as skies try to clear out as well. This
will allow for more cooling during the overnight time frame. As
for high temperatures, highs look to run in the low to mid forties
right now as there will be some solar influence but cooler air
aloft will help to slow how fast we can warm up. But the
increasing amount of daylight and higher sun angle has been
helping us to warm up.

&&

.AVIATION.../ through Sunday / Cloud with ceilings in the 2000 to
4500 ft range this evening, and lowering some overnight as the
main precipitation band moves on shore overnight and early
Sunday. Am not anticipating widespread ceilings below a 1000 feet
through the early morning time frame. Visibilities in the rain
band occasionally lowering to 2 to 5 miles however expect that to
last only a few hours. With the front sweeping through expect some
LLWS along the coast, and some gusty winds into the Lynn Canal
area, that could cause some issues. Turbulence near terrain will
be another flight hazard early Sunday and during the day.

Overall best flight conditions on Sunday should be over the
southern panhandle as most of the frontal energy will be into the
northern portions and starting to dry out as winds swing NW
through the Clarence Strait area during the midday. The northern
Lynn Canal regions will see the toughest flight conditions primary
due to the strong southerly winds in the morning hours and slowly
improving into the afternoon.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...High Wind Warning from 4 AM to 1 PM AKDT Sunday for AKZ318.
     Strong Wind late tonight for AKZ319.
MARINE...Gale Warning for PKZ012-651-652-671-672.
     Small Craft Advisory for PKZ013-021-022-031>033-053-641>644-
     661>664.

&&

SHORT TERM...NC
LONG TERM....SF
AVIATION...Bezenek

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