861
FXAK67 PAJK 231246
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
446 AM AKDT Sun Jun 23 2024

.SHORT TERM...
Somewhat damp short range forecast for Sunday with a stacked,
diminishing low off the coast of Haida Gwaii causing rain chances
for the central and southern panhandle. Easterly flow and
vorticity advection aloft from the aforementioned low combined
with a fully saturated profile will generate just enough lift for
the occasional rain shower. Chances for these showers will
maximize towards the afternoon time frame with a shortwave moving
along the easterly flow. Chances for rain diminish behind the
shortwave with reduced influence from aloft flow. There exists
some uncertainty around the central panhandle with the potential
for downsloping winds prematurely drying the low levels of the
atmosphere. Ultimately, either way, expect mostly cloudy skies
this Sunday and Sunday night. Changes to the forecast include
increasing PoPs around the Petersburg and Wrangell area and across
PoW Island to better represent the weak shortwave trough moving
eastward. Furthermore, reduced PoPs in the northern panhandle as
the stationary front on the Canadian`s side looks to have its
upward motion cut off by a growing ridge aloft.

.LONG TERM...
Extended forecast remains relatively unchanged for next week with
lingering showers Monday diminishing into Tuesday, followed by a
warming and drying trend. For the big picture, the showers to
start the period are due to energy from an easterly wave mentioned
above in the short term discussion. After this, a surface ridge
is expected to build in over the gulf which will bring clearing
skies to the inner channels and overall warmer surface
temperatures due to abundant summer sunshine. Being on the
downstream side of this developing ridge, the one exception to
clearer skies may be the chance of a marine layer developing and
pushing into coastal communities. This will also lead to generally
light winds overall throughout the panhandle. Expect the highest
winds with the usual sea breeze circulations in the afternoon and
evening hours. Being on the downstream side of the developing
ridge, the exception to otherwise clearer skies would be any
marine layer potentially moving into coastal communities.

As is often the case, model guidance is not in full agreement on
the longevity of this blocking ridge over the gulf. However, the
first indications of unsettled weather returning to the panhandle
do not show up until the end of next week as of this forecast
issuance. Overall shaping up to be a fairly dry, warm and not so
windy week to end the month of June!

&&

.AVIATION...
Calm winds and saturated low levels has led to intermittent IFR
cigs and vsbys across southern panhandle TAF sites this morning. A
dissipating upper low over southeastern Gulf will continue to
bring isolated to scattered rain showers across the panhandle.
Anticipating pre- dominate MVFR flight conditions for Sitka over
to Petersburg and southward through much of the day with CIGS AoB
5000ft. Winds are expected to remain less than 10kts through the
period except this afternoon for Skagway which could see sustained
winds up to 15kts. No LLWS concerns for expected at at this time.

&&

.HYDROLOGY...The Chilkat River remains above minor flood stage
today after a brief dip below flood stage yesterday afternoon.
Current forecast is on track to peak around late morning today
after cloud cover inhibited daytime heating and, therefore, snow
melt. The stalled weak frontal feature continues to precipitate
but will diminish through this morning. Aloft ridging will
overwhelm the weak stationary front and begin to clear out clouds
in the extreme northern panhandle. If clouds are successful in
clearing through this morning, warm temperatures from solar
radiation will likely yield increased snowmelt and a flood stage
for Monday higher than currently advertised.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Small Craft Advisory for PKZ641-661.

&&

$$

SHORT TERM...NC
LONG TERM....STJ
AVIATION...NM

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