479
FXAK67 PAJK 250601
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
1001 PM AKDT Thu Jul 24 2025

.UPDATE...Update to Aviation Section for 6z TAF issuance.

&&

.SHORT TERM...Cloudy conditions alongside the occasional rain shower continue
across SE AK as of the time of writing, and look set to remain
omnipresent through the remainder of the week, though with lower
chances of rain showers on Friday.

Satellite and radar imagery show a layer of clouds over much of
the panhandle, with some scattered rain showers moving through the
area. The culprit is a weak low in the gulf, which will decay
into an open trough. The low is bringing continued onshore flow
across the panhandle, which is responsible for the cloud cover
across much of the area. This will likely last through Friday. As
the low weakens on Friday, expect chances of showers to diminish,
though not subside entirely. While the possibility of some breaks
in the clouds do exist on Friday, the cloud deck will likely
remain largely intact. A significantly stronger low enters the
Gulf from the Interior beginning Friday night into Saturday. The
vertically stacked low will send a front sweeping towards the
panhandle, though it is looking likely that the front will stall
offshore, primarily contributing to increased winds in the outer
coastal and gulf waters. For additional information, see the long
term forecast discussion.

Similar to yesterday, cooler 850 mb temperatures aloft alongside
increased cloud cover will help to keep a cap on temperatures,
with high in the 60s and lows in the 50s expected across much of
the area through the next few days. Fog and low stratus
development is expected Thursday night into Friday morning,
particularly along the Gulf Coast and Cross Sound/Icy Strait

Primary forecast changes were to increase cloud cover and add
some chances of PoPs on Friday.

.LONG TERM...Saturday a trough at 500mb will dive into the gulf where it will
close off, stagnating over the next several days, being the
catalyst, and our barrier, of weather across the Panhandle. One
result of this feature will be the deepening of a surface low in
the gulf, driving east-southeast winds along our coast. Current
analysis of the forecasted near 1000mb low and pressure gradient
indicates high confidence for at least strong breezes to near
gales (22 to 33 knots) with probabilistic ensemble forecasts
reflecting a 20 percent chance for gale force; strongest winds of
28 to 33 knots off Cape Suckling and south of Yakutat. Expect
easterly winds to form along Cape Suckling to Cape Fairweather
early Saturday morning with the fetch of southeast winds moving
south through the weekend. Dixon Entrance and Southern Clarence
will start feeling southerly strong breezes Sunday. This low will
sit in the gulf through the next several days, blocking larger
troughs from moving into the Panhandle, and bringing continued
southerly winds/rain.

Touching on rain, all ensemble guidance continues to shift the
main focus of precip south; simply put, much wetter conditions
anticipated south of Frederick Sound. With that said, by-and-large
24-hour amounts for our communities south of Sitka/Petersburg
will remain below 2 inches through the weekend. For folks in the
north, it will be much drier.

&&

.AVIATION...Main aviation concern through the TAF issuance
continues to be the low ceilings and pockets of low visibility.
One change is backing off on LIFR flight conditions for tonight.

Lack of driving flow aloft, accompanying weak surface winds, and
a slight split flow will keep lowering clouds overnight.
Therefore, the widespread VFR and MVFR will slowly degrade into
MVFR to occasional IFR. Expecting IFR conditions to be mostly
present along the coastline, its not out of the realm of
possibility to have these lower conditions in the central and
southern panhandle. The highest likelihood of this is Petersburg
and Wrangell. While LIFR conditions are expected to be present in
the AOR, CIGS AoB 300 ft with IFR VIS is expected to stay
offshore, with IFR CIGS working their way over the western coast.
For the morning hours, currently expecting an improvement on
conditions; however, confidence is low on timing. Due to lack of
significant directing flow, lower conditions may stick around
longer than intended.

&&

.MARINE...
Inside Waters: Cloud cover and less daytime heating associated
with a weak low pressure system impacting the panhandle will
decrease sea breeze potential through the rest of the week. Winds
will remain around 15 kts or less with wave heights up to 3 ft
across the inner channels as this system moves through. N/S
channels will see southerly light to gentle breezes (4 to 10 kts)
persist through Friday, with the exception of Lynn Canal seeing
moderate breezes (11 to 16 kts) decreasing through this morning
and picking back up again slightly this afternoon. A low cloud
deck following the previous front is sitting along the outer
coast, lowering visibilities near Sitka, Klawock, and Yakutat. Fog
going into Yakutat Bay, Cross Sound, and down Icy Strait has
developed this morning and is expected to rise as the sun comes
up. Due to increased cloud cover and PoPs through this period, the
fog may only lift to match the low overcast layer and persist
through the afternoon before lowering back down.

Outside Waters: Westerly winds from gap flow in the western gulf
have dropped to fresh breezes and will continue to decrease
significantly until Friday afternoon when the next front is
predicted to move into the eastern gulf. Associated winds will
first begin to increase along the northern gulf coast before
spreading to the entire outer coast. Sustained winds up to 35 kts
with gale force gusts (34 to 40 kts) are possible with this front,
peaking on Saturday. Wave heights are decreasing from around 8 ft
to 5 ft in the open gulf waters Thursday before increasing Friday
into Saturday up to 10 to 12 feet as the next system moves in.
Currently, wave period is around 7 seconds with a W swell of 2 ft
or less.

&&

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

&&

$$

SHORT TERM...GFS
LONG TERM....AP
AVIATION...NC
MARINE...GFS

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