Ketchikan, Alaska 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

969
FXAK67 PAJK 182253
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
253 PM AKDT Thu Jun 18 2026

.SYNOPSIS...

Key Messages:

- Isolated showers and mostly cloudy skies continue across SE AK
  through Thursday evening as an upper level system moves across
  the panhandle. The far northern panhandle will see more
  consistent light rain begin to dissipate later in the evening.

- Warmer temperatures, sunny skies, and drier conditions are
  anticipated for this weekend as an area of high pressure remains
  over the gulf, with high temperatures reaching into the 70s.

- A region of good heating Friday may lead to stronger convection
  along the Chilkat range and north to British Columbia border.
  and the remains of an upper level features on Saturday cloud
  develop the stronger convection for the Misty Fjords north to
  about Ernest Sound.

&&

.SHORT TERM.../through Saturday night/...As of Thursday
afternoon, a weakening broad upper level circulation is
interacting with a backdoor frontal boundary along the northern
panhandle and southern Yukon Territory. This is leading to a
relatively stationary band of light rain to impact the far
northern panhandle stretching from Skagway westward towards the
northern gulf coast, with occasional showers breaking off and
meandering as far south as Icy Strait. As the interior clears a
bit more today into Friday and flow aloft shifts to be
northeasterly, thunderstorms that form over BC and the Yukon may
have a chance to advect into the far northern panhandle, along
northern Lynn Canal from Skagway to Haines. The most likely
impacts from these would be erratic gusty winds and localized
moderate to heavy rain with potential for ice pellets mixing in.
This will be something that is watched closely as we head towards
the weekend, with a shift in thunderstorm potential further south
closer to the eastern part of Misty Fjords Saturday, though with
lower confidence due to the advancing ridge.

At the surface, the advancing surface ridge combined with daytime
heating has begun to break up the marine layer in the southeastern
Gulf of Alaska as seen via satellite imagery this afternoon. This
trend is expected to continue for the southern panhandle through the
short term period. The central panhandle is also starting to see
some sun poke through breaks in the clouds late this afternoon and
should see a similar trend Friday. Unfortunately the northern gulf
coast will likely see a resurgence of this marine layer currently
visible over the northcentral gulf. It is expected to continue to
rotate around the ridge and push in later tonight, bringing lower
CIGs and potentially mist or light drizzle into Friday morning. This
should retreat offshore with daytime heating later in the day Friday
though.

For Saturday, flow over the interior is expected to become
increasingly meridional out of the north, and the advancing ridge
will continue to dry out the mid and upper levels, particularly for
the central and southern outer coast. Decreasing cloud cover should
allow more seasonably warm summer time temperatures to be felt
across the panhandle this weekend. Forecasted maximum temperatures
are expected to gradually increase heading into the weekend reaching
upwards of the low to mid 70s Saturday, especially for the southern
panhandle. For more on what to expect late this weekend and early
next week, see the long term discussion below.

.LONG TERM.../Sunday through Wednesday/...The region will remain
under the influence of an upper-level ridge through this weekend
and into next week. By Wednesday, an upper- level low is forecast
to track eastward over the region, introducing energy into the
lower levels and increasing PoPs slightly over the central and
northern panhandle. Moderately warm 850mb temperatures will
support weekend highs, and low relative humidity aloft will work
to suppress cloud coverage across the region.

Maximum temperatures will remain elevated into Monday, particularly
across the inland areas, the southern panhandle, as well as near
Hyder, and the Chilkat Valley. Sunday looks to be about as warm
as Saturday, with high confidence that temperatures will remain
the mid 70s in the warmest locations, while general highs range
from the mid to high 60s across the region. A gradual cooling
trend begins Monday, with high temperatures steadily declining
throughout the week.

Remnants of surface high pressure will persist through Monday and
Tuesday, however, winds in the Gulf are expected to shift to onshore
flow, introducing marine layer influence to coastal communities.
Given the preceding warm and dry conditions, current thinking is
that the marine layer will not push far inland. Rain chances will
begin to increase late Wednesday, though precipitation is expected
to remain light and impact the north gulf coast initially.

There remains significant disagreement between ensemble members
on the timing, strength, and formation of a mid-week surface low.
Guidance is trending toward the ridge holding firm, causing any
returning precipitation to be delayed towards the end of next
week.

&&

.AVIATION...Conditions have been generally improving through the
early afternoon hours on Thursday, and look set to continue
improving into the evening. CIGS have climbed to 3000 - 5000 ft
for most of the panhandle, with the lower CIGS generally found
along or near the coast; or in Gustavus. Overnight, anticipate the
potential for some reduction in CIGS to 1500 - 2500 ft for for
the outer coast and parts of the Icy Strait Corridor, depending on
how far a residual cloud deck can rebuild. A pew areas of patchy
fog can`t be ruled out either, although at this time, do not
think that is the most likely scenario. Through the daytime on
Friday, conditions will improve to VFR across the area as a
strengthening ridge builds, although a marine layer building
offshore could move in Friday night. No LLWS concerns during the
time frame, though the potential for an isolated thunderstorm or
two around Skagway cannot be ruled out on Friday.

&&

.MARINE...

Outer Coastal Waters: A strengthening ridge of high pressure will
lead to increasing NW flow along the Gulf Coast. These northwesterly
winds are expected to be accelerated by the coastal terrain,
specifically around prominent capes, causing winds to reach up to
20-25kts by this evening. In the northern outer waters, 15-20kts
are more likely to be expected around Cape Fairweather and Cape
Spencer, while winds in the southern outer waters will have more
time to accelerate up to 20-25kts. This phenomena is expected to
continue through the day Friday before diminishing through the day
Saturday. Through the period , waves are expected to sit around
4-5ft and build up to 8 ft in the southern outer waters with the
acceleration of wind along the coast.

Inside Waters: A weak low traversing along a building
ridge is bringing with it chances of scattered rain showers
through the day on Thursday, before shower chances slowly diminish
on Friday. Prevailing northerly flow for N/S channels will remain
at or under 10 kt for most of the channels through the remainder
of the week and into the weekend. The exceptions will be Clarence
Strait, which will see 10-20 kt NW winds, and northern lynn Canal,
Taiya Inlet, which at times will see S 10-20 kt winds.

E/W channels will see prevailing westerly winds. Sea breeze
influences will strengthen winds during the late afternoon and
evening hours around Icy Strait and Point Couverden to 15-20 kt
through the weekend.

The chance of a few isolated thunderstorms for far northern lynn
Canal and Skagway harbor can`t be ruled out tomorrow (Friday), and
on Saturday for locations east of Ketchikan including Behm Canal and
Portland Canal.


&&

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

&&

$$

SHORT TERM...STJ
LONG TERM...BAS
AVIATION...GFS
MARINE...GFS

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