240
FXAK67 PAJK 170543
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
943 PM AKDT Wed Jul 16 2025

.UPDATE...06z Aviation Update

&&

.SHORT TERM.../through Thursday night/
Key Points:
-Ridge continues over the gulf with dry conditions and mostly sunny
to partly cloudy skies continuing through Wednesday evening.
-A weak front pushes into the SEAK Gulf coast late Wednesday night
into Thursday, returning a round of clouds and light rain to the
northern panhandle.
- A Heat Advisory remains in effect for Hyder until 7pm Wednesday
evening.

Discussion:
No major changes to the forecast package this afternoon as SEAK
continues to enough a period of quieter weather through this evening
under ridging aloft. Looking at obs around the area, seeing
generally mostly sunny to partly cloudy skies with temperatures in
the 60s to low 70s and marine winds around 10 to 15mph.

Brief pattern change incoming tonight into Thursday as an upper
level shortwave trough ejects a weak front into the NE Gulf coast
and coastal panhandle. Not anticipating much, if any QPF with this
system, less than 0.10", mostly falling as a light rain or drizzle
along and north of Frederick Sound by early Thursday morning.
Rain chances decrease once more by Thursday evening as another
surface ridge moves into the panhandle with lows in the low to mid
50s.

Current temps in Hyder hovering in the mid 70s this afternoon, still
thinking we could climb a few more degrees into the upper 70s to
briefly touching 80 over the next couple of hours.  Main forecast
concern for high temperatures will be upper level clouds streaming
in from the NW flow. Held off on issuing Heat Advisory for Hyder
area on Thursday with increasing cloud cover aloft, with highs
reaching into the low to mid 70s.


.LONG TERM...Stacked upper and surface high pressure situated over
the Gulf continues to last into the long range, continuing the
warming and drying trend into the weekend and early next week.
There will be some shortwaves attempting to move through Friday
into Saturday, bringing some chances for light rain along the
northeast Gulf coast, however the surface ridge will rebuild by
Sunday. This will bring a change to a warmer and drier pattern for
early next week, as skies will begin to clear Saturday into Sunday
and rain chances decrease for the majority of the panhandle by
this weekend. Alongside this ridging pattern, some significant 12
to 15 degree C temperatures at 850 mb will be advecting warmer
air into the region Monday and Tuesday and leading to some warmer
surface temperatures. This will be aided even further by the sky
clearing early next week, allowing for areas to get into the 70s
for maximum temperatures. Areas further inland and along the
northern panhandle (such as Skagway and Juneau) may see more of
this warm air advection, with the NBM showing a potential of
20-30% of getting to 80 degrees and EFIs pinging for the panhandle
Monday and Tuesday. Overall something to keep an eye on in the
extended range.

The skies clearing will continue to allow a stronger sea breeze to
develop in some of the inner channels, with winds increasing to 10
to 15 kts if a sea breeze develops. With the setup of the ridging
offshore and a low over B.C., we are also expecting some stronger
westerly winds along Icy Strait and other E-W oriented channels,
with the strongest winds expected during the afternoon. The outer
coastline is expected to continue to see a pattern to support a
marine layer developing, with both the stacked ridge and moisture
availability, so areas along the coastline and into the Icy Strait
Corridor area if pushed inwards by westerly winds may see some
marine layer formation Friday into this weekend.

&&

.AVIATION...

Isolated MVFR to widespread VFR flight conditions continue across
the panhandle Wednesday night. Worst flight conditions remain
along the NE Gulf coast as marine layer remains stubborn, with
CIGS AoA 2000ft. A weak front approaching the NE panhandle will
bring more midlevel cloud cover and low-end chances for drizzle
for locations along the NE Gulf Coast and the northern half of
the panhandle into Thursday morning. With drier conditions at the
surface ahead of this front, fog development is not expected.

Winds should remain 5kts or less through overnight for much of
the panhandle, outside of Sitka and Ketchikan which will continue
to see sustained winds of 10 to 15kts. Sea breeze development
tomorrow for usual areas, though cloud cover from the weak front
will hinder such winds in the northern panhandle. No LLWS
concerns through the TAF period.

&&

.MARINE...
Outside:
Ridging will gradually move over the panhandle through Wednesday
evening with strongest NW-ly winds expected on Gulf coastal side
of Prince of Wales Island up to Strong Breeze around 25kts and
wave heights up to 9ft, diminishing through Wednesday night to
Moderate Breeze with wave heights decreasing to around 7ft as the
ridge begins to slightly weaken. By Thursday afternoon broad
westerly flow over the gulf with northwesterly flow along the
southern panhandle with winds Moderate Breeze up to Fresh Breeze
expected. No significant marine hazards expected at this time.

Inside:
As ridge moves over the panhandle through Wednesday evening,
anticipating East/West oriented channels to see an increase in
winds, with strongest winds expected in Cross Sound, Icy Strait,
and Clarence straight through Wednesday night up to Fresh Breeze,
or around 20kts. For Thursday, expecting generally same conditions
to continue as an upper level system pushes into the northern
panhandle. Strongest winds up to Fresh Breeze expected by Thursday
afternoon in Northern Lynn Canal up through Taiya Inlet and for
Clarence Strait in the Southern Panhandle. Otherwise, marine winds
should remain Moderate Breeze or less through Thursday evening. No
significant marine hazards expected at this time.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Small Craft Advisory for PKZ641-642-661.

&&

$$

SHORT TERM...NM
LONG TERM....Contino
AVIATION...STJ
MARINE...NM

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