Graphical Hydro Meteorological Discussion

518
FXAK68 PAFC 151255
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
455 AM AKDT Tue Jul 15 2025

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through
3/Today through Thursday evening)...

A shortwave trough over the Copper River Basin this morning will
continue to track east, exiting the region later this morning.
Upstream, a more complex pattern is taking hold with multiple
upper-level lows upstream with a weaker ridge nestled between
them, over the southern Bering.

With the exiting trough, the majority of the showers and cloud
cover present over Southcentral yesterday through the overnight
hours will be on the decrease. Southerly flow over the Susitna
Valley this out ahead of a trough/surface front extending south
from a low near Utqiagvik may keep a few lingering showers across
the Talkeetnas toward Broad Pass this morning before this feature
moves east and a shift to a more southeasterly flow takes hold.

South of the upper-level ridge, a deep cut-off low over the
north-central Pacific (south of the eastern Aleutians and Alaska
Peninsula) is slowly advancing northeast. A jet streak along the
eastern side of the low is helping force it northward. As it
continues northward through Tuesday, the ridge over the northeast
Pacific ahead of this low will connect with the ridge over the
eastern Bering out ahead of a western Bering low and move across
southern Alaska. As a result, expect decreasing clouds and
warmer/drier conditions for Southcentral through the day Tuesday.

The track of the north-Pacific low becomes a little more
questionable on Wednesday as the ridge settles over Interior
Alaska and blocks the low from progressing northward. Guidance,
however, is beginning to key in on a track that takes the
deepening surface low into Bristol Bay by Wednesday morning then
steering it toward the Kuskokwim Delta by Wednesday evening.

Given this track, the surface front associated with the low will
move across Kodiak Island Tuesday night and push northward across
the Kenai Peninsula Wednesday, bringing rain and some wind.
Guidance continues to diverge on the progression and strength of
the front as it tries to push inland. This model spread increases
with regard to the track of trailing upper level short-waves
Wednesday night through Thursday. Based on this, expect mostly
cloudy skies with rain along the coast and across the western
Susitna Valley and chance of rain for locations along the lee of
the coastal mountains.

As for winds, small craft advisory level winds will develop over
the western Gulf, with a small area of Gales around the Barren
Islands, ahead of the surface low and front Tuesday night through
Wednesday. The building surface ridge ahead of it will lead to
southeasterly gap winds into Southcentral Wednesday
afternoon/evening. Uncertainty in the strength and progression of
the front lead to low confidence in the strength of gap winds.

-SEB/TM

&&


.SHORT TERM FORECAST SOUTHWEST ALASKA/BERING SEA/ALEUTIANS (Days
1 through 3: Today through Wednesday)...

Everything is on track with the Southwest Alaska forecast on
Tuesday. A trough is currently pushing through the Seward
Peninsula this morning with light rain clipping northern portions
of the Kuskokwim Delta. The rest of Southwest is largely dry,
though widespread cloud cover persists from the overnight hours.
Expect another cool day with minimal rain chances early on.
Tonight into Wednesday, a North Pacific low and its front are
forecast to lift northward into Southwest with what should be an
expanding area of rain and scattered showers from Wednesday
morning into Wednesday night. Thursday should see rain chances
linger across Southwest as a near stationary low over the Bering
sends a wave of low pressure through the region. Precipitation
will be more scattered or even isolated in nature on Thursday, but
coverage should once again encompass all or most of the region.

Farther west, the stationary low over the Bering is forecast to
move little through the weekend. This will keep low stratus and
fog in the forecast for the next several days over the Bering with
a broad region of small craft conditions and gale force gusts
spanning from the Central Aleutians into Saint Matthew Island.
Southwesterly flow around the base of the low will allow for
additional troughs and waves of low pressure to cross the
Aleutians with periods of rain and windy conditions likely through
the end of the week. In the immediate future, a front is quickly
approaching the Central Aleutians and is bringing gusty
southwesterly winds and increasing rain chances through much of
the day today. Behind the front, visibility should improve as rain
clears out, but low stratus will remain in its wake, helping to
keep the sun from making an appearance. The front will eventually
stall over the Pribilof Islands and Eastern Aleutians tomorrow,
quickly dissipating as yet another trough emerges from the North
Pacific. This trough will track from the Eastern Aleutians into
the Alaska Peninsula from Thursday into Friday.

-BL

&&

.LONG TERM FORECAST (Days 4 through 7: Friday through Monday)...

The big picture has a broad upper level low in the Bering Sea and
a building ridge of high pressure extending from the North
Pacific and across South Central Alaska through the forecast
period. For South Central, the building, blocking ridge of high
pressure will promote drier conditions across much of the region.

In the West, the upper level low pressure system generally
remains over the central Bering Sea during the longterm. The main
uncertainty with the Bering low is in regards to how it interacts
with surrounding shortwaves/lows and the speed of its surface
front. The GFS/Canadian solutions would push the surface features
quickly across SW AK whereas the European model now tends to have
the features move slower across the region. Nonetheless, expect an
active pattern out west for the forecast period.

-DD

&&


.AVIATION...

PANC...VFR conditions will generally prevail for ANC, but cloud
ceilings this morning will likely hover around or just below 5,000
ft. Any remaining shower activity should wrap up quickly this
morning, although guidance suggests that ceilings between 12-18z
could dip down to high end MVFR. Up-inlet flow returns this
afternoon as clouds scatter out, which will bring southwesterly
winds that could gust up to 15 kts before diminishing overnight.


&&


$$

213
FXAK69 PAFG 142214
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
214 PM AKDT Mon Jul 14 2025

.SYNOPSIS...A ridge of high pressure breaks down over the Interior
as the first Bering Sea storm of the season brings abundant
rainfall to the West Coast and Western Interior through Wednesday.
Elevated water levels south of the Bering Strait have prompted
High Surf Advisories from Tuesday morning through Wednesday
morning. Smoky conditions across the central and eastern Brooks
Range look to improve Wednesday as fires to the southwest
producing that smoke will likely get much needed rain. Another
ridge builds quickly behind the southwest flow, bringing warm and
dry conditions back for the end of the week across the area.

&&

.KEY WEATHER MESSAGES...
Central and Eastern Interior...

- Southwest winds will continue to bring smoke into the Northern
Interior over the next couple of days, though moderating fire
activity across the western Interior should improve conditions
by Wednesday.

- West southwest winds will gust to 25 mph across the Yukon Flats
Monday afternoon and to 30 mph on Tuesday. Southerly gap winds
through Alaska Range Passes will continue to gust to 30 mph
through Monday.

- Isolated to widely scattered thunderstorms today across the area
and along the Alcan Border on Tuesday.

- Temperatures mainly in the 50s and 60s on Tuesday before warming
back into the 70s through the weekend.

West Coast and Western Interior...

- Southwest flow moving inland brings increasing rain and more
south winds along the coast today through Tuesday night.

- Most areas west of Tanana will see 0.5-1.5" of rainfall through
Wednesday with the heaviest amounts near Nome.

- Increasing south winds across St. Lawrence Island and the West
Coast through Tuesday night before subsiding on Wednesday. Gusts
up to 40 mph are possible through the Bering Strait tonight and
across the Norton Sound on Tuesday.

- Onshore winds 20 to 25 mph south of the Bering Strait have
prompted High Surf Advisories for elevated water levels of 3 to
6 feet above the normal high tide line. Minor beach erosion is
expected.

North Slope and Brooks Range...

- South-southwesterly offshore winds and above normal temperatures
in the 60s or even low 70s continue through midweek.

- Showers and thunderstorms are possible Monday afternoon and
evening from Anaktuvuk Pass eastward across the North Slope.

- Southwest wind gusts of 30-40 mph through Monday night along
the Northwest Arctic Coast between Point Hope and Wainwright.

- A few chances for light rain Monday night through Thursday
before onshore flow and low stratus/fog return late this week.

- Smoky conditions across the central and eastern Brooks Range
look to improve Wednesday as fires to the southwest producing
that smoke will likely get much needed rain.

&&

.FORECAST ANALYSIS AND DISCUSSION...Southwest flow is knocking on
the door to the west and will break down the ridge currently in
place as it pushes east Monday. Point Lay on the northeast corner
of the moisture stream is already seeing rainfall with this. This
is also being influenced by a tight low aloft moving east across
the Chukchi Sea and into the Beaufort. As the moisture pushes
inland, most areas west of Tanana will see 0.5-1.5" of rainfall
through Wednesday with the heaviest amounts near Nome. Onshore
winds 20 to 25 mph south of the Bering Strait have prompted High
Surf Advisories for elevated water levels of 3 to 6 feet above the
normal high tide line. Only light amounts are expected east of
Tanana though as the stream of moisture runs into a building ridge
by Tuesday night. This ridge build quickly through Wednesday over
all of Interior Alaska, bringing a short period of warm and dry
conditions back to the area late this week. A low aloft then
moves to the Kuskokwim Delta on Thursday bringing southeast flow
and more showers, particularly for the West Coast and Western
Interior.

One thing we will be paying close attention to today with this
forecast is the strength of southwest winds at the surface ahead
of the main system moving to the West Coast. Surface high pressure
building into the southern Interior ahead of the ridge aloft will
help amplify these winds, and models suggest a 925 mb jet as
strong as 35 knots over the Middle Yukon and over the Yukon Flats
early Tuesday morning and up to 30 knots on Tuesday evening.
Model soundings suggest these winds stay just above the surface in
the flats, but we can`t rule out gusts mixing down from aloft to
impact the surface. Having increased these winds in the forecast
to have gusts to 30 mph in the afternoons today and tomorrow.

&&

.FIRE WEATHER...Through Wednesday a series of shortwaves and a
front will move over the state bringing widespread light rain
into the central interior and western coast, with much drier
conditions for the western Yukon Flats. Strong southerly winds
will also impact the western coast tonight through Tuesday as a
front makes landfall, pushing eastward through the day. This
feature will help bring cooler temperatures and higher RH, helping
to moderate fire behavior for the fires in the western zones.
Later Wednesday and Thursday another ridge builds across the state
with warm and dry conditions returning to most of the interior.

&&

.HYDROLOGY...No concerns at this time.

&&

.EXTENDED FORECAST DAYS 4-7...By late Thursday, a low aloft is
over southwest Alaska with a trough extended south over the North
Slope. This will bring showers and near normal temperatures across
the northern half of the state. Flow turns back to southwest on
Saturday with more rain inbound for the West Coast, possibly
reaching into the Interior. Ridging may return briefly late next
weekend, but looks to be short lived. Models are in much better
than normal agreement on the overall pattern, precipitation, and
general forecast in the extended period.

Coastal Hazard Potential Days 3 and 4...High Surf Advisory in
effect for the Bering Strait south to Chevak including Norton
Sound for early Tuesday morning through Wednesday morning. Minor
coastal erosion expected with water levels of 3 to 4 feet above
the normal high tide line, except 4 to 6 feet above the normal
high tide line for Stebbins, Unalakleet, Shaktoolik, Koyuk, Elim,
and Golovin.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...High Surf Advisory for AKZ821.
High Surf Advisory for AKZ822-824-825.
PK...Small Craft Advisory for PKZ801-806-853.
Gale Warning for PKZ802.
Small Craft Advisory for PKZ803-805-852.
Small Craft Advisory for PKZ804.
Small Craft Advisory for PKZ807-811-856>858.
Small Craft Advisory for PKZ809-855.
Small Craft Advisory for PKZ810.
Small Craft Advisory for PKZ812.
Brisk Wind Advisory for PKZ813.
Small Craft Advisory for PKZ816-817-851-854.
Gale Warning for PKZ850.
Brisk Wind Advisory for PKZ859.
&&

$$

Chriest/Park (fire)

343
FXAK67 PAJK 151749
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
949 AM AKDT Tue Jul 15 2025

.UPDATE...18z Aviation Update

&&

.SHORT TERM...
Key Points:
- A ridge over the gulf is allowing for dry conditions to continue
with partly cloudy skies.
- High temperatures in the mid to high 60s expected this week.
- Winds remain light in many areas with the exception of afternoon
sea breezes.

Details: Very few changes were made to the forecast for Tuesday. The
developing ridge continues to bring northwesterly winds and drier
conditions across the panhandle. Partly cloudy to clear skies will
allow for temperatures to increase to mid to high 60s throughout
the day. Multiple areas will even see temperatures into the low
70s. Increasing day time temperatures will allow for sea breezes
to form increasing winds for some land areas. Skagway will
experience the largest affect from sea breezes with winds
increasing to 10 to 15 kts in the afternoon.

Currently, as the ridge continues to move closer to the eastern gulf
coast, the pressure gradient has strengthened over N Lynn Canal
increasing winds from Eldred Rock to Taiya Inlet to 15 to 20 kts
early this morning. This gradient is expected to become more west to
east oriented, allowing for winds across N Lynn to slightly decrease
this morning. That being said, sea breezes are still expected to
develop this afternoon.

.LONG TERM.../ Wednesday through Friday / The ridge over the gulf
Wednesday will flatten slightly leading to a more zonal like flow
across the southern gulf the British Columbia by Friday. A weak
trough spreads some light rain into the Northeast gulf coast
Wednesday to early Thursday. The zonal flow may not run across the
southern panhandle Friday and Saturday and Sunday /positions is
variable in the models/, but any shortwaves could potentially clip
the area with precipitation, Friday or Saturday. Short waves are
small, would be fairly quick moving so isolating them may be
issued.

Wednesday should fairly sunny for the inner channels but will be
needing to watch the Marine layer out over the gulf that is pushing
to the coast, and likely trying to spread into the panhandle over
the later part of the week.

&&

.AVIATION...As of 10 am most fog has lifted or at the very least
retreated offshore for TAF sites across the panhandle. The Outer
Coast and western Icy Strait is also dealing with some clouds from
Baranof Island northward partly from marine layer low clouds and
partly from some mid level clouds from a weak disturbance over the
NE gulf coast. MVFR to VFR ceiling here with the lowest being
1500 ft at Gustavus. These lower clouds should diminish from north
to south through the morning with VFR conditions expected for the
rest of the day across the panhandle. The marine layer clouds
should return for the outer coast Tuesday night again possibly
reaching Gustavus again in Icy Strait. As for fog, lower
possibility of it tonight as another day of warmer weather drys
out the lower atmosphere, but best chance is still around
Petersburg and Wrangell again though any that does form should not
stick around as long. Winds remain low for most areas though sea
breeze circulations may produce winds up to 20 kt in some areas
particularly Skagway.

&&

.MARINE...

Outside: As the ridge continues to tighten this morning,
northwesterly winds along the central to southern coast will
increase to NW moderate to strong breezes of 20 to 25 kts. Along
with strong breezes, times of near gale to gale force wind gusts
have a chance of occurring Tuesday evening and night near the
southern coast. Wave heights build to 6 to 8 ft, with the largest
seas west of Prince of Wales Island and near Dixon Entrance. These
increased winds and waves are expected into Wednesday before the
ridge begins to slightly weaken.

Inside: Mainly light to gentle breezes of 5 to 10 kts persist across
the inner channels. An exception to these lighter winds will be
areas that normally experience sea breezes. Specifically, Cross
Sound, Icy Strait, and Lynn Canal will see increases in winds
Tuesday afternoon. The sea breeze will allow winds to increase to 15
to 20 kts along these areas. Along Clarence Strait, Northwest
winds will increase to 15 to 20 kts through the period with the
tightening ridge. These winds across Clarence Strait will remain
elevated through Wednesday, beginning to diminish wednesday
evening.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Small Craft Advisory for PKZ641-642-661-662.

&&

$$

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

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