000
FXAK67 PAJK 262233
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
233 PM AKDT Fri Apr 26 2024

.SHORT TERM.../Friday evening to Sunday morning/...Main challenge
of the short term is a developing system in the Gulf that will
impact the region this weekend. Upper air sites and surface
pressure observations along the Aleutian chain and into the Gulf
are indicating more agreement with the ECMWF; with the GFS
ensemble and deterministic still holding on to a more aggressive
surface winds. The latest forecast has tried to capture the best
of all solutions, highlighting the location and extent of the
surface pressure, while taking into consideration a few high
resolution models placing gale force winds along our southern
Gulf waters, and how stability might impact momentum transfer to
the surface.

For now, expect 25 to 30 knot south southeasterly winds develop
Saturday morning, along with 8 to 15ft southerly seas developing
south of Cape Fairweather by the evening of the 27th. The highest
of these significant heights will be felt south of Cape Decision,
most concern for mariners transiting northwest from Dixon Entrance
along the west coast of Prince of Wales. Seas become a fresh
southwest swell later Sunday, with significant heights diminishing
into Monday.

Total precipitation amounts still continue to look minor for the
south, and very light for the northern and central regions. While
we will see widespread light rain develop south of Frederick,
total amounts still are expected to come in under 1 inch. Our
fantastic COOP sites in the south are reporting near 3 to 3.9
inches of rain through the month of April, with a normal amount
close to 10 to 11 inches for Ketchikan airport. With no strong
atmospheric rivers on the horizon, we will finish the month well
under normal. In the north near Icy Strait expect some light rain
Saturday… a minor inconvenience at best. Totals look to be under
0.5 inches.

.LONG TERM.../Sunday through Tuesday night/...A triple point low
will have developed over the eastern Gulf of Alaska and on an
existing frontal boundary by Sunday. The small craft intensity surface
winds circulating about this low will have already peaked by that
time and precipitation associated with the front will be focused
primarily over the southern half of the Panhandle with rain likely
as far north as Tenakee Springs and Angoon. The low itself will
pinwheel over the southeastern Gulf before ejecting southeast and
out of the forecast area late Sunday night or early Monday. As
this happens, shower activity will diminish from north to South,
leaving scattered to isolated shower activity through Monday night
and a high probability of dry weather and diminishing cloud cover
for Tuesday. The pressure gradient over the inner channels will be
quite weak, so winds will be minimal once the low tracks off to
the southeast. Daytime highs ranging from the upper 50s to lower
60s, but overnight lows are still getting down close to or
slightly below freezing.

&&

.AVIATION...Widespread VFR conditions for the panhandle through
the day Friday with little to no cloud cover aside from a marine
layer that developed and has since moved offshore. Southern half
of the panhandle will see cloud cover return late Friday night
into Saturday along with showers. Potential for marine layer to
affect NE gulf coast overnight, but likely overshadowed by higher
clouds moving up from the south. With approaching system, winds
will switch to be southerly. No LLWS expected during TAF period,
though watching potential for some late Saturday into Sunday for
the southern panhandle.

&&

.MARINE...
Friday afternoon buoys 82,83, and 84 are reporting 3 to 4 ft
southwesterly swell at 8 to 13 seconds. Overnight expect winds to
start to increase from the south and east as a low moves in, with
25 to 30 knot winds lifting into the southern waters Saturday.
South of Cross Sound and Frederick Strait, expect 8 to 15 ft
developing seas, with the highest significant heights south of
Cape Decision and west coast of Prince of Wales.

Seas become a fresh southwest swell Sunday, with significant
heights diminishing through Monday.


&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Small Craft Advisory for PKZ035-036-641-642-661>663.

&&

$$

SHORT TERM...AP
MARINE...AP
LONG TERM....Fritsch
AVIATION...STJ

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