Winter Storm in Alaska, March 7 to 8, 2024

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
351 PM AKST Thu Mar 7 2024

.SHORT TERM.../Through Friday night/...Overall forecast for the
short term has only one major change. Low level moisture from
southerly flow reaching further north than expected looks to hit a
trowal axis on the Canadian side of Haines Highway. The result is
heavy snow for the Haines Highway area. With warm air pushing
aloft over northerly, dry drainage flow on the Haines Highway,
rain and snow will look to continue through Friday morning;
however, snow will be very heavy and wet which will lower snow
totals. Ultimately, the impact may remain the same, as previous
snowfall will have heavy wet snow fall on top, leading to possibly
difficult to manage snow.

Otherwise, for the rest of the panhandle with the exception of
Yakutat, expect gusty conditions, particularly in the southern
panhandle and along the coast. Wind gusts in the southern
panhandle look to maximize tonight to up to 50-55 mph with the
passing of the initial front, then return again for up to 50 mph
winds with the passing of the second band. Most areas will see
rain except for the northern panhandle, with no flooding expected.

.LONG TERM...Upper level troughing will prevail over the gulf
through the period with minor differences in axis placement. This
will maintain an active pattern through the extended as minor
disturbances eject out the base of the trough. Ensembles in good
agreement with a more organized system impacting the region mid next
week with more precip and wind. Given the persistent SWly flow ahead
of this makes the majority of precip expected to fall as rain except
for the higher elevations on the Haines and Klondike highways.
Precipitation recurrence intervals are not that impressive at
this time (1-2 year return), but with above normal temps and a few
ensemble members progging heavier precip WPC maintained threat of
heavy precip and high winds mid next week. Overall no large
changes to the extended forecast.

&&

.AVIATION.../ through Thursday night / Most TAF locations starting
with good ceilings and visibility this afternoon. Rain and snow is
starting to spread in from the gulf into the southern half of the
panhandle (roughly Frederick Sound as of 3 pm Thursday ) expect
this to spread north. Winds will increase as the front gets closer
so coastal communities to see potential wind shear ( Sitka,
Klawock, Ketchikan, and perhaps Wrangell/Petersburg) tonight.
Turbulence near terrain with gusty winds ( gust to 50 kt near the
surface ), will be a hazard planes will need to worry about and
with incoming front as well, there may be an icing issue as
freezing level is above the surface. Expect the ceilings to
decrease overnight and weather to reduce the visibility to near
1000 feet and below 2 miles.

&&

.MARINE...A low pressure system looks to move in from the south
southwest and ride along the coastline to up near Yakutat. Two
frontal bands will extend out, both generating strong gales with
storm force gusts. The first wrap is largely oriented SE to NW
currently moving northward from the southern panhandle. This wrap
will bring winds up to 30 knots in the inner channels, expect
Clarence Strait with gale force winds out of Dixon Entrance. The
second wrap will move up along the coastline and inner channels,
bringing strong gales to the outside, near shore waters and gales
to the north south facing channels. Expect Lynn Canal to be the
uncertainty point here, where southerly winds may not push up into
northern Lynn as quickly as advertised.

As for seas, the initial band looks to build wave heights to 18 ft
nearshore to near 23 ft in the outer coastal waters. Along the
second band, strong winds will churn up seas with wave heights
near 28 ft in the inner and outer coastal waters.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Winter Storm Warning from midnight tonight to midnight AKST
     Friday night for AKZ319.
     Strong Wind from 6 PM AKST this evening through Friday afternoon
     for AKZ323.
     Strong Wind from 6 PM AKST this evening through Friday afternoon
     for AKZ328>330-332.
MARINE...Gale Warning for PKZ031>033-035-036-641>644-661>664-671.
     Small Craft Advisory for PKZ012-013-021-022-034-053-651-652-672.

&&

SHORT TERM...NC
LONG TERM....BC
AVIATION...Bezenek

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