491
FXAK67 PAJK 022100 AAA
AFDAJK

Southeast Alaska Forecast Discussion...UPDATED
National Weather Service Juneau AK
100 PM AKDT Wed Jul 2 2025

.UPDATE...For Aviation and Marine...

&&

.AVIATION...For the 18Z TAF Issuance Update...

We continue hanging on to IFR in a few spots in the inner
channels...particularly around Haines where CIGS are down to 900
ft agl, but just up northern Lynn Canal in Skagway we have VFR in
place. Overall we are seeing more MVFR today than IFR,
particularly south of Juneau and along the outer coast. We expect
to see CIGS lower late tonight again for many areas. IFR concerns
are Juneau and Haines overnight where the moisture is a bit more
locked in on an northeast to easterly general flow, with mostly
MVFR expected elsewhere. /Garmon

&&

.MARINE UPDATE...

Outside: Not much to update at this time. Most changes were to
adjust winds over the inner channels.

Inside: We did adjust winds for the afternoon up a bit for
northern Lynn canal, and adjusted Icy Strait to account for more
westerly flow west of Gustavus and easterly flow towards Rocky
Island and Pt. Couverden. Also, we got a bit breezier at Grave
Point and Midway Island areas of Stephens Passage. As we approach
sunset winds should lay down a bit most areas tonight as ridging
starts to move in. /Garmon

&&

.PREV DISCUSSION....ISSUED AT 505 AM AKDT Wed Jul 2 2025 ...

SHORT TERM...A diminishing surface low and troughing continues to
move southeast into this morning. This will continue bringing
some light rain showers through the morning and this afternoon
with the highest PoPs being across the central and southern
panhandle. The upper level low over the panhandle is still
expected to weaken and be pushed to the east into the main upper
level flow. Throughout the day today the surface ridge currently
over the central Gulf will move to the east to sit off the
coastline by midday, and as it continues moving east will begin to
linger over the panhandle beginning tonight. This feature will
begin to increase some winds along the coast as it approaches
during the day, but will lead to more light and variable winds
across the panhandle by tonight. For more information on the winds
over the Gulf and Inner Channels, check the Marine discussion
below.

Alongside bringing some lighter winds to the area, the surface
ridging building during the day will result in lower PoPs across
the panhandle. There is still the possibility of convective
showers during the afternoon into the evening due to surface
heating, however the majority of the panhandle is expected to just
see light showers or sprinkles by tonight, largely expected north
of Icy Strait Corridor and in the far southeast panhandle. Tonight
is also expected to see some patchy fog to parts of the central
and southern panhandle with potential to drop in visibility to
1SM as moisture remains despite the lower rain chances. Some
parts of the panhandle will also begin to see some clearing in
cloud cover by tonight, particularly in the southern panhandle and
along the coast, which will help bring some warmer temperatures
in the afternoon and evening alongside the potential for some sea
breeze activity as the surface heats up.

LONG TERM...
Key messages:
- A drier trend is expected this weekend with times of light showers
  still expected.
- Temperatures slightly increase to the end of the week into the
  weekend.
- The next low pressure system enters the gulf at the start of next
  week.

Details: Precipitation chances diminish into the weekend as an area
of weak high pressure remains over the eastern Gulf of Alaska. Even
with diminishing precipitation chances, that does not mean that the
panhandle will remain completely dry. Isolated light to moderate
showers will continue across the panhandle. Minimum QPF is expected
with no impacts. Along with light showers, an upper level low will
continue to bring increased cloud cover with broken to overcast
skies. Temperatures at the end of the week begin to increase to near
typical values for this time of year with maximum temperatures in
the mid to high 60s. Low temperatures will remain in the low to mid
50s to end out the week.

Toward the end of the weekend, a low will move north from the
southern gulf increasing precipitation rates. The heaviest
precipitation currently looks to be more focused on the northern
panhandle than the central and southern areas. Another low pressure
moves across the gulf early next week bringing widespread moderate
to heavy rain. Winds with this system look to increase along the
eastern gulf to fresh to strong breezes. With this low pressure
system still a week away, we will continue to monitor it`s
development.

..Evening Update... No major changes and the short term forecast
has remained on track with just a few adjustments to wind speeds
and direction within the inner channels. N. Lynn Canal continues
to have stronger winds, specifically near Eldred Rock into Taiya
Inlet. Increased winds in this area to 15 to 20 kts and will
continue with a strengthened pressure gradient. Otherwise, light
rain continues as a low remains over the panhandle.

AVIATION... A decidedly mixed bag of conditions across the
panhandle through the early morning hours this Wednesday, with
widespread disparities between sites ranging from IFR to VFR
conditions. A decaying low over the panhandle will linger through
the day on Wednesday, keeping chances of rain and lower stratus
decks in the forecast. As the day goes on, do think that conditions
will generally improve across the area, with higher ceilings and
with what fog did form in a few places burning off with the heat of
day. Even then though, some areas will likely struggle to improve
beyond MVFR.

MARINE...
Inside Channels: Winds largely to remain between 5 and 10 kts for
the majority of the inner channels throughout the day today,
decreasing to calm and variable by tonight as a ridge settles over
the panhandle. Cross Sound and Southern Chatham Strait by the
ocean entrance are expected to see W winds up to around 15 kt
throughout the day today before diminishing tonight. Northern Lynn
Canal is expected to continue to see 20 kt winds early this
morning, which will diminish to 15 kt throughout the day today as
the ridge keeps the pressure gradient tightened over Lynn Canal.
This will begin to decrease to 10 kt by later tonight, though if
there is enough clearing in the sky cover and the surface begins
to heat up during the day, the potential for an evening sea breeze
might enhance these winds before decreasing overnight. Some areas
into this morning that may hold onto some 15 kt winds for longer
are Midway Island up through Grave Point, and near Young Bay,
which all should trend downwards in wind speed by tonight.

Outside Waters: Surface ridging over the central Gulf will move
eastward through the morning, keeping winds around 10 kts for most
of the eastern Gulf and along the coast. Winds by the entrances to Cross
Sound and Chatham Strait will continue to be around 15 kts into
tonight as the ridge approaches the coast. Seas expected to stay
around 3 ft across the eastern Gulf. Throughout the day, a low
pressure system over the Aleutian Islands and western Gulf will
push to the east, bringing some 15 to 20 kt winds from the SE into
the central Gulf (around 140W) by tonight. This will also bring
seas of 6 to 7 ft and W-SW swell with a 12 to 14 second period
across the eastern Gulf tonight into tomorrow.

&&

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

&&

$$

HORT TERM...Contino
LONG TERM....EAB
AVIATION...GFS
MARINE...Contino

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