494
FXAK67 PAJK 081344
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
444 AM AKST Wed Jan 8 2025

.SHORT TERM...Couple changes to the ongoing forecast, particularly
in regards to onset timing of precipitation and winds, and
adjusted snow totals for the winter storm warning on the Klondike.
First the timing: ensemble high resolution data has shown a
slowdown trend in the front, typically associated with
strengthening systems. Satellite observations match this thinking
of a slightly slower system, therefore, onset of winds and
precipitation has been pushed back 3-6 hours in most places.
Furthermore, strong WAA in the 850-700 mb layer looks to lead to
unfavorable lift for snow, outside of the ideal dendrite zone.
Therefore, lowered snow ratios beyond period of heaviest snowfall
on the Klondike Highway, after 9 AM Thursday. Combine this with
warming surface temperatures to nearly the freezing level, wet
snow will likely compact onto existing snow in the afternoon hours
on Thursday. While still impactful from dense, wet snow, overall
snow totals will be limited compared to previous forecast. Looking
for snow to begin near midnight on Thursday and still maximize in
rates between 3 AM and 9 AM to nearly an inch per hour.

.LONG TERM...
The strong front that reaches the panhandle late
Wednesday continues to create moderate to heavy rain for the
panhandle through Thursday. The highest rain totals will be located
in the northern panhandle with totals reaching 2 to 4 inches,
potentially more in localized areas and higher elevations. Other
parts of the panhandle will see rain totals of 1 to 2 inches. With
already wet soils, this continued precipitation can cause streams
and creeks to rise to around bankfull. Water ponding in low areas
may also occur. After the initial band of precipitation moves over
the panhandle, expect to see continued rain showers through Friday.
There may be brief breaks in the rain. As this front moves over the
panhandle, wind speeds will increase along the coast and for the far
northern panhandle. Storm force winds along the northern gulf will
be accompanied by waves of 30 to 35 ft in the gulf.

Then the next system arrives late Friday into Saturday bringing the
next round of moderate to heavy rain and stronger winds to the gulf
and panhandle. The far northern panhandle will yet again be the area
of strongest winds and highest precipitation totals. We will
continue to monitor the location and strength of this front. Once
again, there will be a lull period after this front, before another
reaches the panhandle. This continued series of lows into the gulf,
will keep active weather and warmer temperatures for the panhandle
through next week.

&&

.AVIATION...

Mixed bag of IFR to low end VFR flight conditions this morning
across the panhandle under BKN to OVC skies and isolated showers as
a weak wave pushes up the Gulf coast. Anticipating these trends to
remain the same through the afternoon with variable flight
conditions expected across the panhandle with CIGs AoB 4000ft and
intermittent visibilities down to 1 to 2 SM in heaviest showers and
lingering fog. Winds should remain 10kts or less for majority of the
panhandle, outside Haines and Skagway which could see an isolated
gust up to 25kts this afternoon. Flight conditions deteriorate
through Wednesday night with increasing LLWS across coastal TAF
sites as strong front pushes into the panhandle.

&&

.MARINE...Little changes to the forecast in terms of magnitude or
direction; but changes were made to timing as mentioned in
the short term section. Strong breezes to near gales for the
inside waters late Wednesday night, with Clarence Strait hitting
gale in the early hours of Thursday. A stout barrier jet is
expected to develop along the coast as the front moves near the
coastline. Storm force winds located mainly along the NE gulf
coast will develop in the early morning hours of Thursday, then
will be replaced by SE gales in the late morning on Thursday.
Along side great wind speeds, 25 - 30 ft seas, with highest seas
around the NE Gulf Coast, will build with the initial front.

&&

.HYDROLOGY...The latest atmospheric river that moved through on
did bring some rises in local rivers and streams. We still think
it was able to prime the region and start the snowmelt process.
Looking ahead, the next feature will take advantage of the prep
and once again, rises in local streams and rivers are possible as
the next round of moderate to heavy rain tracks through beginning
Wednesday night.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Winter Storm Warning from 9 PM this evening to 9 PM AKST
     Thursday for AKZ318.
     Strong Wind late tonight for AKZ323.
MARINE...Storm Warning for PKZ644-651-652-664-671-672.
     Gale Warning for PKZ033-034-036-641>643-661>663.
     Small Craft Advisory for PKZ021-022-031-032-035-053.

&&

$$

SHORT TERM...NC
LONG TERM....EAB
AVIATION...NM
MARINE...NC
HYDROLOGY...GJS

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