726
FXAK67 PAJK 230004
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
304 PM AKST Fri Nov 22 2024

.SHORT TERM...Through Sat night...Little change to the synoptic
pattern with high pressure over the Yukon and low pressure off the
Pac NW maintaining northerly outflow pattern across the region.
Gradient tightening again attm as low pressure pushes N tightening
the gradient across the region. Nly winds increase again this
evening in response. Signals for strong cross barrier flow and an
inversion present through Sat afternoon with the potential of a
critical level developing kept the high wind warning through Sat
afternoon for downtown Juneau and Douglas. Cool, dry northerly
flow will persist through the period.

.LONG TERM.../Sunday into midweek/... Blocking pattern developing
over the region means that conditions will remain relatively
unchanged through the weekend across the panhandle. High pressure
will continue over the interior, though may shift further east
into British Columbia by the start of next week. This could lead
to a slight weakening of northerly outflow winds, but enhance
outflow winds from NE and easterly oriented valleys and interior
passes.

Any chance of precipitation returning to the panhandle rests on the
blocking ridge over the western gulf breaking down. Ensemble models
are trending toward deterministic guidance of a shortwave moving
down from the Bering Sea, bringing some precipitation chances to
the northern half of the panhandle. Current forecast reflects
optimistic changes that precipitation (as snow) will return,
bringing anywhere from a trace to 6 inches of snow in 24 hours to
the Icy Strait corridor. However, due to the current strength of
the ridge and how deep the dry layer within the channels currently
sits, certainty regarding any moisture penetrating far into the
inner channels is low. At this time, leaned more towards a drier
solution for the panhandle, with up to 2 inches expected.

Following the shortwave moving down, uncertainty on whether SE AK
moves into an active pattern or back to outflow is high. At this
point, the current forecast keeps temperatures low with widespread
PoP chances around 40%. Unfortunately, this best represents the
uncertainty on the pattern going forward.

&&

.AVIATION...VFR conditions with clear skies and full visibility
will continue here in SE AK. Winds will be the main concern in the
forecast. While the high in Canada shifts SE, wind speeds at the
surface will more-or-less stay steady. Areas of LLWS will continue
with the highest probability of LLWS being near Sitka, and in the
inner channels, especially in the areas near interior passes.

&&


.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Strong Wind until 9 PM AKST this evening for AKZ318.
     High Wind Warning until 3 PM AKST Saturday for AKZ325.
MARINE...Gale Warning for PKZ012-013-022-031>034-643-644-651-661>664-671.
     Small Craft Advisory for PKZ011-021-035-641-642-652.

&&

$$

SHORT TERM...BC
LONG TERM....NC
AVIATION...GJS

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