Petersburg, Alaska 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

394
FXAK67 PAJK 261820
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
1020 AM AKDT Thu Jun 26 2025

.UPDATE...Updated Aviation section with issuance of 18z TAFs.

&&

.SHORT TERM.../through Thursday night/...Another cloudy and rainy
day is in store for SE AK. That being said, most of the rain will
be in the southern panhandle.

Key Messages:
-Lingering onshore flow and approaching front will keep the clouds
 and rain in the short term forecast for SE AK.
-Cooler-than-normal afternoon highs are expected due to the extra
 cloud cover.
-Any concern for elevated winds will be associated with a front
 that will move in later tonight into tomorrow.

Details:
500mb low over the southern Bering Sea is keeping the active
weather in place for SE AK. As the low over the Bering keeps
spinning, the panhandle will continue to see wave after wave of
precip and brief elevated winds.

The area will see two embedded 500mb shortwaves pass over the area
today into tomorrow. At the surface, this would mean continue rain
and rain showers over the area today, with a more organized front
expected later tonight into tomorrow. This front will push a band
of rain from south to north through the area.

This front will also bring brief elevated winds and wind gusts.
That being said, these elevated wind speeds won`t be too high,
with highest speeds around 10 to 15 mph in the more open areas.
Sheltered areas will experience lighter winds, even as the front
tracks through.

.LONG TERM...The mid and extended range is mainly dominated by a
broad upper trough over the state that is anchored by a cold upper
low over the Gulf of Alaska through much of the period. The
general trend for the forecast under this pattern is wet, cool,
and cloudy. This will particularly be true for the late week and
weekend as a front will be pushing through the area at that time.
Currently, no significant signals for any abnormally wet or windy
weather, but the light rain will be persistent from Friday through
Sunday as first the primary front moves in on Friday followed by
a secondary shortwave on Saturday with another shortwave following
the same track on Sunday. Expecting around an inch or two of rain
total for the three day period with the highest amounts over the
southern panhandle. Winds will also be somewhat elevated during
the same time period though again nothing very significant.
Expecting around 20 kt for max winds in the gulf as each of these
features move through. Inner channels winds were raised a little
to around 15 kt (20 kt in Clarence Strait) especially with the
shortwave moving through on Saturday.

By early next week, an upper high begins to build in the Alaska
interior, possibly forming a rex type blocking pattern over the
state. For SE, however the upper low persists in the gulf and will
continue to produce onshore flow over the region through at least
mid week. Possibility of another shortwave coming up from the
south on Monday afternoon bringing another period of rain for the
area. Otherwise the general trend is still damp for the first half
of the week with possible drying conditions by later in the week.

&&

.AVIATION...Into this morning we continue to see predominantly
MVFR flight conditions around the panhandle as the current
shortwave passes through, followed by some showers. This will
bring us quite mixed conditions throughout the day with these
flight conditions switching between low and high-end MVFR, VFR and
IFR throughout the day as showers move through. MVFR conditions
will occasionally be dropping to IFR mainly across the central and
southern panhandle with CIGS between 1500 and 2500ft and VIS
dropping to as low as 2 to 4SM. The northern panhandle and up
along the northern Gulf coastline have begun to clear up to VFR
flying conditions, though are beginning to see some drops to MVFR
as this shortwave moves through late this morning, bringing some
2500 to 3000 ft CIGS.

Some locations in the central panhandle through Icy Strait
corridor may see some improvement to VFR for a few hours this
afternoon, before CIGS drop again by this evening as a front
approaches from the southwest. The central and southern coastline,
and majority of the southern panhandle, will stay at MVFR for the
majority of the day however as showers will quickly transition to
the front moving in tonight, not giving much of a break period
for flying conditions to improve. The highest confidence remains
for a period of VFR conditions in the afternoon for the northern
panhandle TAF sites, primarily locations north of Icy Strait
corridor. Locations such as Haines, Skagway, and Yakutat will hold
onto these VFR conditions for longer into the overnight hours.

Winds are expected to remain around 5 kts or less and variable
through tonight. The only stronger winds will be in Skagway,
though they will begin to decrease from 10 to 15 kts this morning
to light and variable this afternoon into tonight. Ketchikan will
also see some 10 kt winds throughout the day, which will decrease
by this afternoon to 5 kts before increasing again as the front
pushes through late tonight. There are no concerns at the moment
for LLWS for this approaching system tonight, the main concerns
just being the fluctuation between flight categories throughout
the day today.

&&

.MARINE...
Outer Waters: Outer waters have swung to the south to southeast,
with the central gulf buoy reporting around 15 knots. Going into
the rest of the day, a front will approach the panhandle,
bringing SE wind speeds up to 20 knots in the gulf. As the front
swings inland and northward Friday, southerly gulf winds will
lower to around 10 to 15 knots with speeds like that lasting into
the weekend.

Inside Waters: Early morning reported wind speeds range from
light winds to around 15 knots from a southerly direction. Reduced
visibility due to fog and low clouds are seen on webcams near Cape
Fanshaw. Other areas around the panhandle are clear of fog as of
4AM. Expect winds across the inner channels to be on the lighter
side today with afternoon speeds to be around 5 to 10 knots for
most of the area, out of a south to southeasterly direction. For
tonight into tomorrow, as the incoming front swings northward,
wind speeds in the inner channels will increase, in association
with the front, to upwards of 10 to 15 knots with locally higher
wind speeds possible. Additional waves of wind are likely this
weekend with speeds upwards of 10 to 20 knots at times.

&&

.HYDROLOGY...
With the exception of the Chilkat River, no big
widespread hydrology concerns at this time. 24 hour rainfall
amounts will be greatest in the southern panhandle at around a
quarter to half inch. From the EURO and GFS ensembles, the 90th
percentile (so 10% chance of occurring) is up to three-quarters
to one inch. Even the higher end amounts are no cause for concern
at this time.

As far as the Chilkat goes, recent rainfall in addition to the
river levels already close to flood stage, have caused the river
to cross over into flood stage again. Still thinking rainfall
should be coming to an end in the northern panhandle this morning.
So given that and the recent history observation patterns, decided
to keep the Chilkat above flood stage until 4PM Thursday afternoon
so a Flood Advisory product will be in effect today.

&&

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

&&

$$

SHORT TERM...GJS
LONG TERM....EAL
AVIATION...Contino
MARINE...GJS
HYDROLOGY...GJS

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