722
FXAK67 PAJK 191441
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
641 AM AKDT Sun May 19 2024

.SHORT TERM...Cloud cover continues to build as a front
approaches the panhandle, and widespread rain will return to SE AK
through Sunday.

Aloft, a vertically integrated low in the western gulf has begun
to weaken as occluding takes place. The low still remains fairly
respectable by dry-season standards, with a depth of approximately
526 decameters at 500 mb per operational guidance as of the time
of writing. While the low itself will slowly fill in through the
next few days as it moves into the eastern gulf before sliding
off to the SE, its associated cold front is already at SE AK`s
doorstep. Cloud cover is increasing, and a few occasional showers
have begun ahead of the main system. Warm air advection ahead of
the front will encourage widespread stratiform precipitation to
move through the area from W to E through the day on Sunday, with
precip amounts of between 0.25 and 1 inch of rain anticipated
through Sunday night. By early Monday morning, the front itself
will have moved through the panhandle, with the now rapidly
occluding off the coast of Cape Spencer and moving off to the SE.
Precipitation rates will drop off as the decaying system races off
to the SE, with breaks in the clouds for much of the area Monday
night, and widespread clearing skies by Tuesday. For additional
details, see the long term forecast discussion.

The surge of southerly warm air advection ahead of the approaching
front will see winds increase across the area. Anticipate gale
force and small craft conditions for the outer coastal waters, and
small craft or near small craft conditions for the inner channels
as winds and waveheights increase through Sunday. For land-based
locations near sea level, winds will be strongest in the northern
half of the panhandle and in outer coastal communities.

The primary changes to the forecast were to broadly increase
wind speeds in the inner channels and for land-based locations,
as well as to solidify the track of the approaching low through
the next few days. Some minor adjustments were also made to sky
cover and temperature grids during the morning hours of Sunday.


.LONG TERM.../ Monday through Thursday night / Progressive pattern
continues across the gulf and Southeast Alaska. Residual showers
on Monday are being moved out of the area by a ridge across the
gulf Tuesday into early Wednesday. With potential breaks, may need
to watch for patchy fog development, however, do not have
mentioned in forecast at this time.

The next front in the pattern will be moving across the gulf
Wednesday and looks to be pushing into the panhandle Thursday.
This front is not looking as strong as the mid week one, so just
anticipating light rain and minor increase in the winds.

&&

.AVIATION...An occluding cold front moves across the Panhandle
today bringing moderate rain and a few hours of LLWS along the
coast. Currently we are VFR across most areas, expect MVFR CIGS
as the front moves over later this morning. Could see some
isolated clearing this evening but expect MVFR and pockets of IFR
Monday morning.

&&


.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Frost Advisory until 7 AM AKDT this morning for AKZ320-321.
MARINE...Gale Warning for PKZ651-652-664-671-672.
     Small Craft Advisory for PKZ012-013-032-033-053-641>644-661>663.

&&

$$

SHORT TERM...GFS
LONG TERM....Bezenek
AVIATION...AP

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