458
FXAK67 PAJK 090600
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
1000 PM AKDT Thu May 8 2025

.UPDATE...Aviation section for 06z TAF issuance.

&&

.SHORT TERM...An active weather pattern will continue as short
waves rotating around a slowly decaying vertically stacked low in
the central gulf continue to move across the panhandle through
the duration of the week. While a respectable amount of rainfall,
given the current time of year is anticipated, no flooding is
expected.

In particular, two separate waves arriving on Friday look to
provide the greatest impacts to SE AK. The first of these will
arrive through Friday, moving up from the S, bringing with it
fresh to strong breezes across the central inner channels along
with a wave of precipitation across the panhandle. The second wave,
arriving Friday afternoon through Friday evening, will bring with
it similar conditions, albeit with winds along the outer coast
reaching near gale force.

The rainfall will continue through the first half of Saturday,
until a weak frontal boundary associated with the second wave
advances E across the panhandle, bringing drier weather in its
wake. For additional details, see the long term forecast
discussion.

.LONG TERM...Much better consensus between ensemble members regarding
timing and location of heaviest rain rates for the central and
southern panhandle. Saturday will see the final of multiple waves
moving up along the front in the eastern gulf. An embedded wave will
be near Prince of Wales Island, and push into the Yukon over the
morning hours. Associated with this wave will be moderate to heavy,
with rain rates maximizing around 0.1 inches per hour. Southerly
winds look to remain steady at around a fresh to strong breeze in
the very early hours of Saturday. Behind the wave moving northward
is a weak cold front in the eastern gulf, which is expected to move
to the east slowly over the course of Saturday. In the post frontal
environment, winds and rain are expected to diminish quite rapidly.
Good confidence that the cold front will push as far east as
Petersburg down to Hydaburg, but some solutions are keeping the
moisture tap over the southern panhandle well into Saturday
afternoon. While dynamics aloft do not look to support heavier
rainfall beyond Saturday afternoon, lingering rain in the area may
continue into Saturday Night.

Sunday will see the first day in southeast Alaska with widespread
clearing skies and warmer temperatures. Skies look to clear from
northwest to southeast, so areas in the southern panhandle will
likely see clearing later in the day. Expect temperatures in the mid
to upper 50s with some areas possibly exceeding 60 degrees.

For Monday, a shortwave aloft looks to come racing across the
northern gulf, associated with a broad upper level low in the Bering
Sea. An associated surface low will extend a fast moving front over
the panhandle, bringing more rain and wind to the area. Not
expecting winds higher than a fresh breeze, mainly for the Icy
Strait area and north. Main area of concern would be the quickly
dropping pressure in northern B.C. and pressure rises behind the
front could bring up to stronger winds of 20-25 knots to northern
Lynn Canal, Taiya Inlet, and Skagway.

&&

.AVIATION...Ceilings will remain at MVFR for the central and
southern panhandle. The northern panhandle will remain at VFR
until late tonight into Friday morning, as the next trough moves
precipitation up from the south. Prevailing MVFR conditions will
then continue through Friday with ceilings decreasing to 1500 ft
and visibilities as low as 4SM. The southern panhandle will also
begin to see some gusty conditions in the late morning through
Friday afternoon. LLWS over the southern panhandle will begin
tonight as the next wave moves north. By Friday morning, parts of
the central panhandle also begin to experience LLWS. At that time,
Friday morning, widespread wind shear of >25 kts will be located
across areas south of Icy Strait. The most prominent LLWS will be
off the coast of Baranof Island, with around 40 kt winds at 2000
ft around Sitka.

&&

.MARINE...Outside Waters: Wind speeds along the outer coast build
up to 25 kt by late Thursday night into Friday morning, while a
second short wave moving N later in the day on Friday brings
sustained winds up to 30 kt. up to 35 kts. Wave heights will
remain around 8 ft before building late Thursday night along the
southern coast to around 10-11 ft. Conditions will rapidly improve
on Saturday in the wake of a frontal passage associated with the
second short wave.

Inside waters: Winds in most of the inner channels Thursday
evening remain around 10 to 15 kt out of the S, before increasing
Thursday night into Friday as the next wave approaches, reaching
20 to 25 kt. Elevated winds then last through Friday and into
early Saturday before rapidly diminish through late Saturday
morning and into Saturday afternoon. The exceptions will be
Clarence Strait, which is already at 25 kt from the S as of late
Thursday afternoon and which will remain so until early Saturday
afternoon. Conversely, Lynn Canal will become variable Thursday
night before flipping out of the N on Friday, and only going S
Friday night.

&&

.HYDROLOGY...Two separate shortwaves embedded within a decaying
frontal band will bring with them 1"-2" across much of the area
Friday through Saturday. Although no flooding is expected, river
rises are likely, particularly for the southern panhandle and
outer coastal areas - locations which could potentially see in
excess of 2 inches, should sufficient S to SE flow in the lower
levels prove to be present. Higher totals are also possible at
elevation.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Gale Warning for PKZ664.
     Small Craft Advisory for PKZ035-036-641>644-661>663-671.

&&

$$

SHORT TERM...GFS
LONG TERM....NC
AVIATION...Contino
MARINE...GFS
HYDROLOGY...GFS

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