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FXAK67 PAJK 190701 AAA
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
259 PM AKDT Sun May 18 2025

.SHORT TERM...A surface ridge continues to move through the
panhandle Sunday afternoon, with winds in the southern inner
channels finally shifting out of the south as a gale force low
slowly approaches the far southern panhandle and Haida Gwaii later
tonight. Despite drying conditions at the surface, an upper level
trough has provided enough lift, combined with daytime heating, to
produce isolated showers across the central panhandle. Overall these
showers remain light and have been observed from Juneau in the north
all the way down to Ketchikan. These showers are expected to taper
off in the late afternoon, while a band of showers extending from
the gale force low will impact the far southern panhandle late
tonight.

With models shifting the system slightly further south, rain totals
remain relatively unchanged, though coverage of expected
precipitation has been adjusted accordingly. 24 hour max
precipitation amounts still are forecast to remain below 0.75
inches, though locally higher amounts at high elevations on eastern
PoW are possible. The northern panhandle will see northerly outflow
winds develop as the low approaches and gradient tightens from north
to south. Strong wind gusts up to 40 mph are expected for the far
southern panhandle as this system approaches and the primary band of
showers moves through later tonight. For more information on
potential wind impacts, see the Marine discussion.

For Monday, this system will continue to weaken as it moves in over
Dixon entrance and attempts to push into BC, stalling over the far
southern panhandle and Clarence Strait. As such, winds across the
panhandle will slacken through Monday afternoon as ridging and
onshore flow builds.

.LONG TERM...Continuing from the short term, the decaying low over
the far southern panhandle looks to devolve into an open wave
trough, which will receive reinforcement from thermal troughing over
BC through midweek. This means afternoon showers remain a
possibility, particularly for the central and southern panhandle.
Though like Sunday, these should be relatively light and sparse.

Otherwise across the panhandle temperatures will remain seasonably
warm and, dodging any showers, will remain relatively dry. Afternoon
sea breezes should become more prevalent for a majority of the
panhandle with diminishing cloud cover, but otherwise no significant
wind concerns on the horizon.

Looking towards midweek, there is still some uncertainty with a
Bering low that is expected to enter the western gulf Wednesday.
Models have begun to pull back on the eastward movement of this
system as well as its overall strength, with a slightly stronger
ridge behind it helping to steer it further south into the gulf.
This would serve to lower chances for any moderate precipitation
impacts to the panhandle until possibly next weekend. Stay tuned for
further updates throughout the week.

&&

.AVIATION.../Through 06z Tuesday/ For the northern half of the
region...Skies have cleared out in a majority of locations with
winds calming down. VFR CIGs will prevail through the night with the
chance for CU development towards the end of the period which could
bring isolated showers. Winds have flipped to their drainage or
northerly direction as the low to the south approaches. Through
Monday, offshore flow will bring sunshine and sea breeze directions.

For the southern half of the region...Broken ceilings with clear
visibility have allowed the southern panhandle to remain comfortable
in VFR for the last few hours. The system has moved into the SE gulf
and will bring precipitation and rain showers through the period.
Winds have shifted out of the SE for most places and have
strengthened as the front pushes over. Not expecting too many
significant issues with regards to CIGS and VIS as the day
progresses, though conditions may slightly deteriorate for some
locations as precipitation begins. LLWS in the far southern
panhandle will also be a factor with SE to E winds of 25 to 35 kt at
2000 ft for PAKT and PAKW.

&&

.MARINE...A Gale force low continues to move east toward Haida
Gwaii. This low will increase winds and waves near the southern
panhandle as it continues to approach and weaken Monday morning.
Winds along N to S facing channels will slightly increase tonight
before staying light to moderate around 5 to 15 kts tomorrow.

Outside Waters: The 19z ASCAT pass shows winds up to 30 kts east of
the Gale force low. As this low moves closer to the panhandle, a
tightening pressure gradient will strengthen winds west of POW and
south of the panhandle, near Haida Gwaii, to ESE Gale force winds of
35 kts. Wave heights will build to 10 to 14 ft subsiding Monday
morning. This low will continue to move east and diminish through
Monday. At that time, a ridge builds over the Gulf of Alaska
creating a change in wind direction becoming WNW Tuesday. Winds will
also remain around 10 to 15 kts through late week. The next low
pressure system enters the gulf late this week.

Inside Waters: Winds will become northerly this afternoon into
tonight as a low pressure system moves to the south of the
panhandle. An inverted trough at this time will increase winds for
north to south facing inside channels with gusts up to 25 kts. Late
tonight, Clarence Strait will receive the strongest winds of 20 to
30 kts and gusts up to 40 kts. After the low diminishes and moves
farther east, inner channel winds will weaken and once again become
southerly through Monday. After Monday, gentle to moderate breezes
of 5 to 15 kts will be the predominate winds across the area. An
exception is N. Lynn Canal that will experience a tightened pressure
gradient increasing winds to 15 to 20 kts during afternoons and
evenings this week.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
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PUBLIC...Strong Wind from 10 PM AKDT this evening through late
tonight for AKZ328.
MARINE...Gale Warning for PKZ641-661.
     Small Craft Advisory for PKZ036-642>644-662>664-671-672.
-- End Changed Discussion --

&&

$$

SHORT TERM...STJ
LONG TERM....STJ
AVIATION...Ferrin
MARINE...EAB

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