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FXAK67 PAJK 162252
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
252 PM AKDT Sun Jun 16 2024

.SHORT TERM...Similar to yesterday, the story of today is a slight chance of
thunderstorms near Haines Customs and White Pass, and a marine layer
moving ever further into the inner channels overnight into Monday.
Current thoughts is the marine layer near the surface (foggier
conditions over water) will reach towards the entrance of Glacier
Bay before encountering continental air and moving aloft. For Sumner
Strait, An increasing robust dry airmass looks to inhibit marine
layer movement inland and will likely remain as a broken layer of
low clouds stopping around Port Protection. By morning, the marine
layer will retreat yet again back to the gulf, meanwhile causing
a thermal gradient between the rapidly increasing temperature of
the inland areas and the gulf waters. The result is an increase in
westerly winds in areas such as Icy Strait and possibly Peril
Strait.

For thunderstorms: yet again, initiation in Canada has sparked
several thunderstorms with a northerly to northeasterly direction.
At this time, the storms looked to be cut off by the Coast
Mountains. A few may make their way on the extreme northern
portion of the panhandle and possibly into Misty Fjords and Hyder.
Judging from model soundings, a majority of the energy and shear
appears to be cut off even if storms make it over the terrain into
the AOR.

.LONG TERM...Summer continues across SE Alaska through the first
half of the week, though more active weather is on the horizon.
Get out and enjoy it while you can.

A ridge will continue to hover over SE AK through Wednesday, with
the axis slowly moving E over the Gulf and across the area. Dry,
with afternoon sea breezes in the inner channels is the main theme
over the next few days. By Thursday, a weak wave will attempt to
advance through the ridge, bringing with it chances of rain,
though operational guidance is likely overemphasizing PoP chances
with this system. Anticipate fairly minimal QPF totals and wind
impacts, if the system isn`t largely eroded away by the ridge
itself. By the end of the week, an extension of a closed low over
the Aleutians attempts to form into a longwave trough and move
into the Gulf, bringing some onshore flow, cooler temperatures,
and increasing PoPs through the weekend. Think that there is a
good chance that much of the energy will move S of the panhandle,
but still anticipate at least some chances of rain for the area.
Afterwards, some clearing is increasingly likely for the latter
half of Sunday or Monday, though this is not set in stone, with
the GEPS being more pessimistic.

Threats to coastal and gulf waters remain low through Thursday,
with our swells significant deep ocean wave heights remaining
largely under 8ft. With that said, stout 15 to 20 knot northwest
winds along the coast will bring short period wind driven waves to
the west coast of Prince of Wales and into Dixon Entrance.

&&

.AVIATION...VFR conditions continue for most of the inner channels.
The exception to this is areas near the outer coast where a marine
layer has lingered around today. Conditions near this layer vary
from VFR down to pockets of IFR. These conditions will last through
the evening with redevelopment of this layer expected tonight.

Otherwise, winds should be calm once any sea breezes settle.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...None.

&&

$$

SHORT TERM...NC
LONG TERM....GFS
AVIATION...GJS

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