489
FXAK67 PAJK 181413
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
613 AM AKDT Sat May 18 2024

.SHORT TERM...A dry day and clearer skies are in store for much of
the panhandle on Saturday, barring a few showers for areas south
of Frederick Sound - though chances of precip begin returning to
the forecast tonight ahead of an approaching system.

Aloft, a blocking pattern situated over the interior and the Yukon
will continue to weaken and disintegrate as the primary flow
pattern continues to redirect itself across the Gulf of AK. A low
traversing from the Bering Sea into the Gulf as of the time of
writing is providing the downstream energy for a 554 decameters
ridge (500 mb) which will briefly rebuild across the Gulf in the
wake of a system which moved SE of the panhandle through Friday
night.

At the surface, this will translate into clearing skies and fairly
warm daytime temperatures for many locations. Although a few
showers are possible S of Frederick Sound through the morning
hours, these will give way to increasing breaks in the clouds as
their associated low moves into Vancouver. Winds for many
locations across the inner channels will be fairly variable as a
lull in strong synoptic level flow over SE AK results in sea
breeze effects becoming more pronounced. Some locations could have
stronger wind speeds, like Point Couverden, Lynn Canal, and
Skagway, along with some of the ocean entrances and outer coastal
waters. Cloud cover will begin to rebuild Saturday night through
Sunday, along with the chances of a few showers Saturday night.
These will prove to be the harbinger of an organized system which
will bring with it stratiform precipitation as a front moves
through Sunday and Monday. For additional details, see the long
term discussion.

Minimal changes made to the forecast. Some adjustments were made
to wind speeds and directions to add detail to a few areas which
experience ocean-effects, and think that low temperatures on
Saturday night will need to be closely watched, as the potential
exists that they could be cooler in some locations than guidance
currently indicates.


.LONG TERM.../ Sunday through Wednesday night / Frontal band
sweeps through Eastern Gulf of Alaska and the Panhandle. Gale
force winds ahead of the front into the Northeast Gulf Coast, and
then Small Craft Advisory to the inside waters. Trailing showers
and the remains of the low in the Northeast gulf will get moved
into the panhandle Monday. Rain / showers will be tapering off
Monday headed into Tuesday.

High pressure builds into the gulf Tuesday then moving towards the
panhandle Wednesday as yet another front spreads into the western
gulf Wednesday. This pattern of a quick moving and weak systems
moving through followed by the ridge rebuilding over the gulf
every few days persists into the mid to late next week period.

&&

.AVIATION...Marginal VFR conditions along the Coast Mountains
south of Cape Fanshaw due to residual shower activity. Otherwise,
clear & 7. Weather moves back in on Sunday with instrument
conditions from the Icy Strait corridor northward & along the
northeast Gulf Coast with precipitation across all of Southeast
Alaska. No turbulence concerns for the next 24 hours.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Gale Warning for PKZ652-672.
     Small Craft Advisory for PKZ651-671.

&&

$$

SHORT TERM...GFS
LONG TERM....Bezenek
AVIATION...Fritsch

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