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FXAK67 PAJK 170004 AAA
AFDAJK

Southeast Alaska Forecast Discussion...UPDATED
National Weather Service Juneau AK
404 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.

&&

.HYDROLOGY...A flood advisory remains in effect for the Chilkat
River through 4 AM Wednesday morning. Continued warm temperatures
will enable snow melt to result in the river remaining near or
above minor flood stage. The river height will diminish during the
evening time frame before increasing again during the overnight
and morning time period, becoming higher each day.

&&

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

&&

$$

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

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