060
FXAK67 PAJK 121433
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
533 AM AKST Wed Feb 12 2025

.SHORT TERM...Clear, cold and dry weather continues through
Wednesday, although a change to the pattern is finally on the
horizon.

The upper level ridge which has been steering systems away from
the panhandle has started to erode. As it falls apart, systems are
having increasing success advancing into the Gulf of Alaska. One
of these systems - a low current located over the central Gulf as
of the time of writing, will slowly meander into the NE Gulf on
Thursday, bringing with it a weak frontal band which will reach
the outer coast. Although the frontal band itself isn`t
impressive, with its biggest impacts largely confined to chances
of showers by late Wednesday night, and stronger winds in the
inner channels, by Thursday, it will prove to be the herald of
more robust systems advancing through the weekend.

Temperatures will continue to exhibit a diurnal trend through
Wednesday, with low temperatures Wednesday night once more likely
to reach the single digits for some more wind-sheltered areas.
Winds will begin increasing into Thursday as the weak frontal band
contributes to a strengthening pressure gradient, strengthening
outflow winds across the board. Main forecast changes were to
decrease winds in many areas through the day on Wednesday,
although notably expect that some East/West outflow channels like
Taku Inlet and the Stikine River will continue to exhibit elevated
winds and wave heights in comparison to their surrounding
channels. Some upper level cloud cover will begin to build in from
the outer coast, and move inwards by late Wednesday into Thursday.

.LONG TERM...Thursday a broad open longwave trough will close off
over central Alaska, with convergence over Canada reinforcing a
surface high pressure draped across the Northwest Territories. In
the gulf, this feature will pull a surface low north, tightening
the pressure gradient and increasing outflow winds, particularly
in east opening river entrances and east to west channels. The
published forecast has tried to showcase these locally higher
winds, especially in Portland Inlet where storm force winds are
becoming more likely. Over the weekend an extensive but weakening
low will lift in the gulf, driving gale force easterly to
southeasterly winds along some of our coastal waters. Expecting
18-25ft southeast short period waves from Dixon Entrance to the
central gulf in response to this wide fetch of winds, with wave
energy moving northwest towards the Kenai Peninsula; expecting
this energy to spread into the northern coast impacting the Prince
William Sound - Cross Sound transit.

Precipitation increases by Friday as the aforementioned low lifts
into the gulf, steering some moisture into the region. CW3E
products highlight the limited moisture to work with; with that
said, we dont need a lot of moisture to drive snow impacts. Given
the cold temperatures in place, expecting some snow at first
before rain. A few inches of snow for Yakutat/northern-coast
Friday, with similar snow impacts for the central and southern
Panhandle later Saturday. Per norm, further interior areas like
Petersburg and Wrangell will have a hard time scrubbing out cold
air, with longer duration light snow likely. For the northern
Panhandle there isnt a strong signal of moisture moving past
Frederick Sound but we will have to monitor guidance trends
closely for moisture placement.

Active weather continues through the middle of next week. Guidance
is aggressive in warming airmass transitioning precipitation type
to liquid. Kept forecast towards cooler NBM 10-25th percentiles
resulting in a slower transition mid next week.

&&

.AVIATION...Most places continue to see VFR conditions this
morning with clear skies and light winds. But a marine layer has
developed over the outer coast of the Gulf and is trying to work
its way into the Inner Channels. This is evident in morning
satellite imagery showing clouds developing in Icy Strait as well
as Lynn and Chatham. Areas that see clouds develop will likely
experience CIGs down to MVFR conditions. The thing to watch today
will be to see if the clouds that are moving in this morning
dissipate during the day with solar heating, or if they persist
across the area. Aside from the potential lowered CIGs, the flying
weather continues to be a similar story as the last few days
elsewhere.

&&

.MARINE...Inner channels: Similar to the previous day, light
winds continue across most of the inner channels. Areas that have
increased winds of fresh to strong breezes include many inlets
along the eastern panhandle. Some of these include Taku and
Stikine Inlets. Winds in the inner channels begin to strengthen on
Thursday as outflow winds intensify.

Offshore: Wave heights of between 8-10 feet are expected off the
outer coastal waters as a low arrives in the Gulf of Alaska. As
the low moves into the northeast gulf Thursday into Friday,
anticipate increasing wind speeds and wave heights. With this
low, gale force winds near Cape suckling will develop Thursday
night increasing wave heights past 12 ft into the weekend. This
weekend, another low will then enter the gulf from the south
increasing wave heights to 20 to 25 ft.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Strong Wind from this evening through late tonight for AKZ318.
MARINE...Small Craft Advisory for PKZ641>644-651-652-661>664-671-672.

&&

$$

SHORT TERM...GFS
LONG TERM....AP
AVIATION...SF
MARINE...EAB/GFS

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