Petersburg, Alaska 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

475
FXAK67 PAJK 100645
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
1045 PM AKDT Sat Aug 9 2025

.UPDATE...to add the 06Z aviation discussion section...

&&

.SHORT TERM...
Key messages:

- Moderate to heavy rain continues tonight into tomorrow for areas
  across the panhandle as a low moves into the panhandle.
- Winds increase for coastal areas and inner channels to sustained
  fresh to strong breezes of 15 to 25 kts.
- Another low pressure system enters the gulf and moves toward the
  panhandle through Sunday.

Details: A front continues to move over the panhandle before the
parent low moves into the panhandle tonight. Rain has lightened
behind the initial front, but times of moderate to heavy rain
continues for some areas. Rain rates will once again increase as the
parent low reaches the panhandle this evening. The heaviest rates
tonight will fall from Baranof Island to Wrangell and along Stephens
passage. Along those areas, rain rates around 0.1 inch per hour are
expected to resume. The low bringing this heavy precipitation then
moves inland and dissipates Sunday morning. Light to moderate
precipitation will then continue for the panhandle afterwards.

Winds along the northern inner channels have slightly decreased late
morning into this afternoon. In the southern inner channels,
sustained strong breezes of 20 to 25 kts have continued along
Clarence Straight. Winds will increase into tonight as the low
reaches the panhandle tightening the pressure gradient. Sunday
morning, winds along the gulf and southern inner channels will begin
to decrease. Whereas, northern inner channels from Stephens Passage
to Lynn Canal will continue to see elevated winds through Sunday.
This is due to a strong south to north pressure gradient as a low
moves north of the panhandle and a ridge sits to the south.

The next system moves into the gulf Sunday night into Monday.
Although not as strong as the system that is moving through today,
rain totals will be around 0.5 to 1 inch for the central panhandle.
Through Sunday into Monday there is a 70% chance of 1 inch of rain
or more to fall across the central panhandle.

.LONG TERM...Key messages:
- Lingering light rain into Tuesday from a quick moving system to
  start the week.
- Winds on a downward swing across the inner channels Tuesday/Wednesday.
- Ridge builds in the gulf through midweek with drier conditions
  across the panhandle Tuesday and Wednesday.
- Rain to

Details: Continuing from the short term, the path of the fast moving
system on Monday will lead to increased winds in the inner channels
once more before gradually decreasing. Winds in the gulf will
pick up out of the southwest once more reaching up to strong
breeze (23 - 27 knots) before gradually dropping to fresh breeze
(17 - 21 knots) as a ridge builds over the gulf and flow along the
outer coast turns northwesterly.

This surface ridge coupled with an upper level ridge will bring
drier weather for Tuesday and Wednesday across the panhandle, along
with less cloud cover and warmer daytime highs up to around 70,
particularly for the southern panhandle. Model spread reigns
supreme for late next week, but as of this discussion, sometime
Thursday looks like when we can expect rain and cloud cover to
make their presence know again with a potential low forming in
the gulf.

&&

.AVIATION.../Until 06Z Monday/...As far as CIGs & VISs, primarily
flight conditions within the MVFR/IFR range are expected through
the period as an impactful weather system moves through. Some
areas may dip into LIFR at times under heavier precipitation and
lowered cloud CIGs. Winds will be rather gusty through the night
tonight for the southern Panhandle up to PAJN with a tightened
pressure gradient. Starting late Sunday morning, winds will pick
up, becoming gusty for northern Lynn Canal, including PAGY & PAHN,
from the same cause as the low moves northeastward into the
southern Yukon territory of Canada. This will last through the
end of the TAF period. As far as LLWS is concerned, areas from
PAJN & southward are anticipated to experience magnitudes up to
around 35 kt out of a generally southeasterly to southwesterly
direction, centered up at around 2 kft, into Sunday`s morning
hours.

&&

.MARINE...
Outside: Winds in the northern gulf continue to SE winds ahead of
the front. As the front passes Saturday late afternoon, these winds
will shift southwesterly. These winds along the gulf, will overall
remain around 15 to 25 kts into tonight. This will bring elevated
southwesterly seas of 11 to 13 ft at 9 to 11 seconds for most of the
coast, with a strong SW swell that will persist for the next few
days. Winds will begin to decrease Sunday morning, to 10 to 15 kts,
as the low pressure system moves inland. Another low pressure system
then makes it`s way across the gulf Sunday night into Monday. This
system will once again bring increased winds of 20 kts for
primarily southern coastal areas.

Inside: As the front continues to move through the panhandle, from
north to south, the strongest winds remain in Clarence Straight.
Along Clarence Straight, sustained southerly winds of 20 to 25 kts
developed this morning and have continued into this afternoon. As
the front continues to move across the panhandle, and the low moves
inland, expect winds along north to south facing channels to
increase. The strongest of these winds will be tonight into Sunday
from Icy Straight to Stephens passage and northward into Lynn Canal.
Lynn Canal will see the strongest winds with sustained winds of
20 to 25 kts and gusts up to 30 to 35 kts. Wave heights of 3 to 4
ft will be widespread through this system. These winds and waves
will diminish Sunday evening through Monday morning.

&&

.HYDROLOGY...
Rainfall will continue across the area as multiple systems move
into the panhandle through the weekend. As of Saturday afternoon,
heaviest rainfall rates have decreased across the panhandle for a
brief reprieve, with Storm Total Amounts around 0.75 to 1.0 inch
across the panhandle since Friday. Through the rest of Saturday
evening and into Sunday morning, anticipating rain rates to
increase once more across the area as secondary front swings
inland, with the heaviest rates will be around Baranof Island
eastward towards Wrangell and up along Stephens Passage with
rainfall rates up to 0.10 to 0.15 inches likely. Forecast remains
on track with rainfall accumulations up to 3" expected through
Sunday morning, with locally higher amounts up to 4" at higher
elevations and westward facing terrain. Rises of rivers and
streams are expected across the central and southern panhandle,
but no major flooding is expected at this time. Precipitation
rates and coverage will decrease moving into Sunday afternoon.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Small Craft Advisory for PKZ012-022-031-053-641>644-651-652-
     661>664-671-672.

&&

$$

SHORT TERM...EAB
LONG TERM....STJ
AVIATION...JLC
MARINE...EAB
HYDROLOGY...NM

Visit us at http://www.weather.gov/Juneau