Area Forecast Discussion Issued by NWS Juneau, AK
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FXAK67 PAJK 250504 CCA
AFDAJK
Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
251 PM AKDT Sun Sep 24 2023
.SHORT TERM...Frontal band that moves over the AK Panhandle
through the day finishes crossing over the NE Gulf Coast overnight
while pulling to the west. Rain diminishes with some fog
developing overnight and into the early morning. Northerly winds
over N-S oriented channels increase as a strong low that as off
the Washington State coast moves northward while weakening
increase the pressure gradient. As this low moves in and stalls
off the Haida Gwaii coast SE Gulf winds pick up to gale force with
more rain moving in over the southern panhandle along with
increasing overland and inner channel winds. Off shore flow over
the north central areas will limit rainfall early Monday. Warm air
advection will behind the fronts will increase temps for Monday.
Forecast has remained consistent and new model runs indicated only
minor differences.
.LONG TERM.../Tuesday through Sunday/...Ensemble guidance
continues to show the low off of Haida Gwaii start to track north
after stalling briefly on Monday, weakening as it moves into the
Gulf of Alaska. While slight uncertainty remains with regards for
an exact track and how fast the low weakens, there is good
agreement that the southern panhandle will see increased winds and
rain chances with this system by Tuesday morning. Winds along the
southern inner channels and outer coast will respond as the low
moves northward through the day. Farther north, winds will
increase as well but not as strong as what is expected for the
southern panhandle. As mentioned in the short term, some gale
force winds are expected when the low is off of Haida Gwaii, but
these should weaken to small craft as the system pushes further
northward. The best chances of rain continue to remain along the
southern and central panhandle with this system while the NE gulf
coast and northern panhandle have lower chances of seeing rain
until late Tuesday into Wednesday. As of this forecast, the low is
then expected to weaken and briefly stall a second time off of
the central gulf coast before slowly diminishing as it pushes
eastward late Wednesday into Thursday. The rate at which this
system weakens and dissipates is still uncertain, though continued
rain chances are expected for the central and parts of the
southern panhandle through Thursday morning.
Heading into the weekend, conditions continue to look typical of
fall for SE Alaska. Temperatures will continue to remain mild to
cool while rain will be on and off across the panhandle with
Friday being the best chance for a break. At this time though,
models continue to show no consistent signal for significant
weather for SE Alaska in the mid and long term period.
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.AVIATION...-- Changed Discussion --
Expect flight conditions to be primarily VFR or a
MVFR condition this evening across the panhandle. An advancing
trough over the northern panhandle is causing some light rain in
that area, while the main frontal band rotating about the low south
of the gulf brings rain and wind through the southern and central
panhandle through the evening and overnight. Expecting to see
clearing sky conditions, behind the main front. This may lead to
patchy fog from the south central to north central panhandle
overnight into tomorrow morning. In areas that develop the patchy
fog morning flight conditions could be as low as IFR.
Low level winds with the second front may also result in some
turbulence near terrain or LLWS for Prince of Wales Island and the
southern inner channels this evening and early Monday morning-- End Changed Discussion --
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.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Gale Warning for PKZ641-661-662.
Small Craft Advisory for PKZ012-013-022-033-036-642>644-651-663-
664-671-672.
&&
$$
SHORT TERM...PRB
LONG TERM....STJ
AVIATION...Bezenek
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