Graphical Hydro Meteorological Discussion

455
FXAK68 PAFC 081228
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
428 AM AKDT Wed Jul 8 2026

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3)...

A shortwave trough over the western Copper River Basin is running
up against a second wave draped over Southwest Alaska and Kodiak
Island this morning. Rain continues across Kodiak Island north to
the southern tip of the Kenai Peninsula and across the Talkeetna
Mountains and Susitna Valley. Between these two features, bands of
showers have developed in weak low-level convergence and moisture
advection. A coastal ridge, combined with lower pressure across
Southern Alaska, has allowed southeasterly gap winds to persist,
especially through Turnagain Arm and across West Anchorage. For
Palmer and the Copper River Valley, these winds have diminished
overnight and become less gusty.

The trough over Southcentral will elongate, getting stretched by
both the westerly flow across Southcentral and the trough over
Kodiak Island sliding east into the Gulf of Alaska. This will
allow showers to continue through this afternoon across the
Susitna Valley and eastern half of the Kenai Peninsula. Scattered
showers will also remain possible across the Cook Inlet region.
Southeasterly gap winds will pick back up by around noon, albeit
with less intensity than that of yesterday, across typical
locations.

Models continue to struggle with the evolution and track of the
next shortwave moving from Yukon, Canada over the Alaska Range and
interior Southcentral for Thursday. Placement of the trough will
dictate location of the steadiest precipitation through Thursday.
As of Wednesday morning, the track of this wave looks to be from
Paxson southwest across the southern Susitna Valley.

As the trough and surface low sweep across the Alaska Peninsula
Wednesday and into the southeastern Gulf Thursday, it will pull
the aforementioned trough to the south along with it. Drier and
warmer conditions are expected for Thursday and Friday with most
locations reaching high temperatures in the mid to upper 70s, with
near 70 for Homer, Seward, Valdez, Kodiak, and Cordova as a
warmer northerly flow aloft develops along with gusty northerly
gap winds.


&&


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

A low pressure system in the southeastern Bering Sea continues to
push its front through Southwest Alaska today. As a result,
expect rain to continue across much of Southwest today before it
begins to taper off this afternoon and evening from west to east.
By this afternoon and evening, the low center will have
transferred its energy across the Alaska Peninsula (AKPEN) to form
a new low in the Gulf of Alaska around Kodiak Island.

For Thursday, an upper-level shortwave, originating from the
interior of the state, will drop southward across the Kuskokwim
Valley. Due to the timing of this feature arriving Thursday
morning, the atmosphere looks relatively stable and therefore the
lightning threat will be very low. There is still some uncertainty
on the ultimate track this feature will take. However, as it
appears now, most rainfall from this system will fall from
Sleetmute and east to the Western Alaska Range. Rain tapers off
Thursday night into Friday morning with some leftover showers
lingering along the Western Alaska Range.

The next weather-maker features more uncertainty with regards to
the track and progression of a North Pacific low that is poised to
move along the Aleutian Chain and eventually into the Bering Sea
for the rest of Friday and into Saturday. More on this in a
moment...First off and setting the stage for this North Pacific
low is a relatively strong ridge across the western and central
Bering this morning. This ridge axis, currently centered across
the Western (Shemya) and Central (Adak/Atka) Aleutians, will shift
eastward across to the Eastern Aleutians
(Nikolski/Unalaska/Akutan) and Pribilof Islands by Thursday
morning. This will open the door for the North Pacific low
mentioned above to sends its front to Adak/Atka and
Nikolski/Unalaska/Akutan by Thursday afternoon and evening. The
strongest winds are expected to be sustained small-craft (with
gale-force gusts) southerly to southwesterlies in the North
Pacific marine zones south of Nikolski/Unalaska/Akutan. Expect
light to moderate rain also to accompany this system.

Now for the uncertainty...There details are murky on how far
north this system will lift into the Bering Sea on Friday and its
ultimate track on Friday evening into Saturday with regards to the
mainland Southwest forecast. If the system system remains farther
south along and tracks along the Aleutian Chain, expect the
heaviest rain and gusty winds to remain confined more to the
Aleutian Chain and AKPEN. Conversely, if the system ends up taking
a more northern track into the Bering, expect a more expansive
coverage or rain into the Pribilof Island and into Southwest
Alaska Friday into Saturday. Stay tuned to the forecast as updates
are made and details hopefully become more clear with time on the
track of this system.

&&


.LONG TERM FORECAST (Days 4 through 7: Saturday through
Tuesday)...

The long term forecast starts on Saturday with troughing and
frontal systems in the Gulf of Alaska. A front will move into
Mainland Alaska on Saturday, bringing rainfall and elevated wind
speeds. Rainfall is expected in Southcentral by Sunday as
troughing moves into the Gulf of Alaska. Confidence on the
intensity of rainfall is uncertain at this point and could be
lighter or heavier depending on how strong the the fronts are.
Sunday will see an upper level ridge start to build back into the
Bering, the ridge will build through Tuesday, likely leading to
widespread low stratus or fog for the Aleutians and Pribilof
Islands. By Monday, the current thinking is that the upper trough
will move further south into the North Pacific from the Gulf of
Alaska. Once this happens, it is likely that conditions across
Southern Alaska will begin to dry out with lingering showers
remaining. Tuesday will be similar to Monday with skies clearing
out further for mainland Southcentral and Southwest Alaska.
Daytime heating could lead to showers over inland areas.

-JAR

&&


.AVIATION...

PANC...Southeasterly Turnagain Arm winds will persist today,
weakening a bit this morning and then reintensifying this
afternoon. While winds wont be quite as strong as yesterday, gusts
to 25 kts will be possible through much of the day. There will be
showers in the vicinity of the Terminal this morning, with a
chance for a shower to encroach on the terminal. Despite the
rain, VFR conditions should persist through the TAF period.
Turnagain winds will dissipate overnight and a seabreeze will take
over, causing winds to turn southwesterly by mid morning
tomorrow.

&&


$$

061
FXAK69 PAFG 081356
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
556 AM AKDT Wed Jul 8 2026

.SYNOPSIS...
Warm weather continues in the northern half of Alaska with
isolated to scattered thunderstorms expected in the northwest on
Wednesday. In the southern half of Alaska it will be cooler and
wetter, with between a quarter and a half an inch of rain possible
for a large swath of the southern Interior through Thursday.
Westerly winds in the West Coast and Western Interior will
strengthen Wednesday evening through Thursday evening. Friday and
Saturday, the Interior will warm back up ahead of a new system
arriving on the West Coast.

&&

.KEY WEATHER MESSAGES...
Central and Eastern Interior...
- Warm and dry conditions persist in the northern Interior through
Saturday. Daytime temperatures in the mid 70s and low 80s are
expected. A heat advisory is in effect for the Yukon Flats for
highs near 85F again Wednesday. Temperatures cool in the
southern Interior late Wednesday into Thursday.

- Heavier rain is expected in the southern Interior Wednesday
evening into Thursday. A swath from Fortymile Country to the
Tanana Valley to the Kuskokwim Valley may receive up to a few
quarters of an inch of rain and up to an inch or more in the
Alaska Range.

- Isolated thunderstorms will be possible across much of the
Central Interior Wednesday afternoon. They are expected to
develop mostly over the Ray Mountains and northern White
Mountains, but may also form over high terrain farther east.

- Southerly winds gusting up to 50 mph through the Alaska Range
passes will die down by Wednesday afternoon.

West Coast and Western Interior...
- Scattered to isolated thunderstorms are expected Wednesday
afternoon in the Western Interior from the Middle Yukon Valley
to the Kobuk Valley.

- Heavy rainfall along the northern slopes of the Western AK Range
and in the Upper Kuskokwim Valley could support rain totals
ranging from a quarter of an inch to over an inch.

- Temperatures will begin to cool slightly with daytime highs in
the mid to upper 70s in Interior valleys on Wednesday and
dropping lower into the 70s Thursday. Along the coast, highs
will be in the 50s/60s.

- Stronger southwesterly/westerly winds will develop Wednesday
afternoon and gusts up to 20 mph will be possible throughout
the western Interior Valleys through Thursday night.

North Slope and Brooks Range..
- Hot temperatures will continue through Thursday. Daytime
temperatures warm into the 50s near Utqiagvik to the low 80s on
the eastern Arctic Plains. A heat advisory is in effect for the
Arctic Plains for Thursday.

- Max temperatures on the North Slope will be closer to 70 on
Friday and Saturday, and into the 60s on Sunday.

- Scattered thunderstorms will be possible in the Brooks Range and
Western Arctic Plains Wednesday. Then they will shift to the
Central Brooks Range on Thursday and the eastern Range on
Friday.

&&

.FORECAST ANALYSIS AND DISCUSSION...
A pair of lows, a 544 decameter in Bristol Bay and a 549 dam over
the Panhandle, are responsible for cooler and wetter conditions
in the Southern Interior Wednesday and Thursday. A ridge
positioned over Canada but extending over Northern Alaska, is
keeping the North Slope and Yukon Flats hot and dry. Between
them, thunderstorms will develop. There are two main swaths of
precipitation, one for each low. The first will arrive in the
Western Alaska Range/Kuskokwim Valley Wednesday morning and rain
through Wednesday evening. NBM 25th and 75th percentile create a
range between 0.25-0.50" at the low end and 0.75 to 1.00" at the
high end. Using McGrath as a sample point, many ensemble model
members are forecasting between 0.5 and 0.75 inches with a few
model runs at an inch or more. I expect a widespread area in the
Kuskokwim Valley of between a quarter and three quarters of an
inch of rain with some areas where it is heavier seeing up to an
inch on Wednesday. The second band of precipitation is associated
with the low over the panhandle. It comes in from the east over
Fortymile Country a bit later on Wednesday afternoon and continues
to wrap around west into the Tanana Valley and Alaska Range on
Thursday. Rain totals range between a quarter of an inch to an
inch for much of the Interior south of Circle in a 24 hour period.
The eastern Alaska Range could see around 2 inches due to upslope
flow. Apart from the two main bands of precipitation, showers and
thunderstorms will develop in the afternoon. The best chance for
scattered thunderstorms on Wednesday will be in the Western
Interior, from the Middle Yukon Valley, near Galena, and north
into the Western Brooks Range. Isolated thunderstorms will have a
chance to develop over the higher terrain in the rest of the
northern Interior as well. The Yukon Flats and Eastern North Slope
will remain dry and hot again today with temperatures peaking
near 85F in the Yukon Flats and near 80 north of the Brooks Range.

Thursday, as the Bristol Bay low moves east into the Gulf of
Alaska, a ridge builds in from the Bering which will connect with
the ridge over the Northeast. Weather will continue to be warm in
the northern parts of the Interior, reaching the upper 70s and low
80s. Isolated thunderstorms will develop southeast of the new
ridge axis, in the Central Interior. Widespread rain in the
Southern Interior will dissipate through throughout the day as the
low in the Gulf moves away, but it will mean cooler temperatures
in the southern Interior on Thursday, likely below 70F.

Friday, thunderstorm coverage shifts eastward along with the low
in the Gulf and ridge which is becoming more established over the
State. Isolated thunderstorms will develop in the eastern
Interior and eastern Brooks Range Friday afternoon. Temperatures
will begin to increase for the majority of the Interior, back
into the upper 70s/low 80s. Broad scale troughing over the West
Coast and Western Interior will keep temperatures cooler, in the
60s.

&&

.FIRE WEATHER...
As a low pressure system centered over Bristol Bay this morning
tracks east towards the Gulf of Alaska, cooler temperatures and
ample moisture will continue to advect north as gap winds ramp up
through Alaska Range passes first followed by a broad increase in
synoptic winds later today into Thursday regionwide. Following
another active thunderstorm day across Western Alaska yesterday with
over 3,000 lightning strikes, another unsettled day is on tap today
with another round of scattered thunderstorms extending from the
Lower/Middle Yukon north through the Brooks Range and onto the
Southern Arctic Plains. Cooler temperatures and cloudier conditions
building in farther south will work to limit convection, with
onshore winds along the West Coast limiting thunderstorm development
out that direction.

A Fire Weather Watch remains in effect for the Interior Kotzebue
Sound and Northwest Interior north of Galena to Ambler, which will
be coordinated with AICC later today on a potential upgrade to a Red
Flag Warning. At this time, isolated to scattered coverage looks
more likely farther inland up through the western North Slope
region. While temperatures will see some relief over the southern
half of our CWA, highs in the 70s to low 80s will continue for the
Northern Interior north onto the Southern Arctic Plains. While the
North Slope sees temperatures moderate later in the week, the
warmest conditions across our region are expected to continue for
the Yukon Flats.

As the aforementioned low tracks east into the Gulf on Thursday, a
northeast oriented upper level ridge will quickly fill in behind.
This setup will allow for northeasterly flow to develop across the
Southern Interior Wednesday night into Thursday, supporting more
scattered to widespread light rain showers. With this precipitation
will be a large cloud shield, further limiting convection and
pushing best chances north of the Tanana to around the Fortymile,
North-Central Interior, and Brooks Range. By Friday, the ridge axis
will shift to being directly overhead and will lead to warming and
drying conditions across Northern Alaska, with any isolated
thunderstorms over the Central/Eastern Interior and Brooks Range
trending more isolated. Looking ahead, there is increasing
confidence towards another upper level trough working east from
Siberia Friday into the weekend, with more widespread precipitation
chance and cooler temperatures expected regionwide as thunderstorm
coverage becomes increasingly isolated.

&&

.EXTENDED FORECAST DAYS 4-7...Saturday through Tuesday.
Generally, models are in agreement that there will be an upper-level
low near the Bering Strait on Saturday morning, though the ECMWF has
weak ridging over the SE portions of the state while the GFS has
ridging over the NE. Both models have the ridging weakening
throughout the day and the GFS has a weaker low being pushed into
the Gulf of Alaska Saturday night while the ECMWF doesn`t. However
the ECMWF does have the low that was near the Bering Strait going
into the Gulf on Monday morning while the GFS keeps it over the
Bering Sea and eventually move of mainland Alaska. This differs from
what earlier model runs were hinting at, so it is possible that this
forecast may change once again.

Limited impacts are expected for either of these solutions, both
producing scattered showers over the state throughout the period.
Uncertainty remains regarding precipitation timing, location, and
amount. Cooler, but relatively seasonal temperatures are still
expected.

Coastal Hazard Potential Days 3 and 4...None

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...Fire Weather Watch for AKZ916-918-919-928.
Heat Advisory for AKZ833.
Heat Advisory for AKZ806-808.
PK...Small Craft Advisory for PKZ804.
Small Craft Advisory for PKZ805.
Small Craft Advisory for PKZ852.
&&

$$

Troyke
MacKay - Fire Wx
Extended - Lewis

932
FXAK67 PAJK 080559
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
959 PM AKDT Tue Jul 7 2026

.UPDATE...Issued several new small crafts and a marine weather
statement regarding a gust front moving northward. At time of
writing, it is currently approaching the Eldred Rock area. Highest
uncertainty is if winds will extend into the Glacier Bay area, or
if lack of heating due to dusk will reduce the thermal gradient
enough to be non impactful. Leaned towards it moving into the
Glacier Bay area. Gusts associated with this front may reach up to
30 knots.

&&

.AVIATION...00z TAFs...Showers are expected to largely be on the
downward trend, with gusty winds diminishing going into the
overnight timeframe. In the wake of the second front that moved
through the central and southern panhandle, mostly VFR to MVFR
conditions with the occasional convective shower. No longer
expecting any lightning to be associated with any of these
showers, the area of lift looks to be too low to provide any
significant ice for lightning development. Going into tomorrow
morning, a front does approach from the southwest, once again
bring down CIGs AOB 2500 ft with a slight increase in winds and
additional rain showers.


&&

.PREV DISCUSSION......

SYNOPSIS...

Key Messages:

- An organized band of stronger showers is over Baranof and Prince
of Wales Island and will continue to move inland Tuesday evening

- A slight chance of isolated thunderstorms will be possible,
with potentially gusty outflows from the stronger cells

- Active weather continues midweek as shower potential continues
Wednesday and another front moves into the central and southern
panhandle through the evening

SHORT TERM.../ through Thursday night / The with the inner
frontal band wraps spinning showers along the coast line of
Baranof Island to Cape Edgecumbe and then westward into the gulf.
Some of the showers are stronger with locally gusty winds, the Low
will drift ESE into the southern panhandle overnight before
falling apart. Mid level support and orographic lifting may allow
stronger convection sufficient to spark a few isolated
thunderstorm for the southern portion of the panhandle this
evening and perhaps Wednesday afternoon towards the Misty Fjords
area of the panhandle.

Should see showers tapering off over the south, but the next
incoming trough across the southern gulf to the southern panhandle
Wednesday evening/night. The northern gulf and panhandle is
looking drier and the front is sweeping to the area, but not over
the northeast gulf.

LONG TERM.../Friday through Sunday/...After the low pressure on
Thursday brings a front across the southern half of the panhandle,
this low will move southeastward and dissipate quickly as it gets
near Haida Gwaii overnight into Friday morning. The remnants of
this low will keep some precipitation chances into the morning for
the far southern panhandle Friday. As for the northern panhandle,
a low to the NE of the panhandle in Canada will bring a band of
showers southeastward Friday. The timing and extent of this
easterly wave is still uncertain at this time, associated with
some disagreement on the timing of a shortwave and upper level
band of vorticity moving through the area around the upper level
low in Canada, and the overall presence of the upper level low
into the end of the week as some ridging attempts to build over
the interior and Yukon. The confidence as of now is for the wave
to push through the northern panhandle from Skagway and Haines
down Lynn Canal through Friday morning, into the central panhandle
by the afternoon hours, before just grazing the coastal mountains
of the southern panhandle by the evening.

This uncertain pattern continues into the weekend as the
possibility of some weak easterly waves impacting the panhandle
lasts through Sunday night with this main low sitting to the NE.
None of these waves appear to have as much confidence past
Friday`s shortwave, but with the ridging building over the Gulf
and panhandle into this weekend, the chances for drier weather and
breaks in the cloud cover is higher for this weekend across much
of the panhandle as this more benign pattern sets in.

AVIATION...Active pattern from an aviation standpoint for the southern half of
the panhandle while a line of showers work their way eastward
towards Prince of Wales Island. Looking at NUCAPS soundings out
ahead of the front, there is some evidence of less than expected
lapse rates between 850-500 mb, with good confidence, however, this
may change with the 0z Annette sounding. Regardless, embedded
thunderstorm development, particularly in southern PoW and southern
Clarence Strait including Ketchikan is possible due to orographic
lift. Guidance does indicate that CAPE values greater than 300 J/kg
are possible ahead of this system, partly with assistance of daytime
heating around the Ketchikan area. Any thunderstorms that do develop
are expected to be associated with wind gusts up to 35 knots, CIGs
AoB 2000 ft, and moderate rain showers with visibilities less than 4
SM. Behind this convective system, unstable conditions will still be
present without a clear lifting mechanism; however, it is possible
to see some occasional rain showers.

MARINE...
Inside (Inner Channels): Winds across the inside waters mainly
remain southeasterly around or below 10 kts with the exception of
Clarence Strait and Taiya Inlet. These areas have seen southerly
winds increase to around 20 kts late this morning into this
afternoon. Along with this, a slight chance of thunderstorms
continues into this evening for southern areas. The main impact will
be erratic gusty winds that can quickly increase. Todays higher
winds will remain into tonight before the overall wind trend is
diminishing winds. The next front starts to make its way through the
gulf tomorrow. This will once again increase winds. Again the main
areas, with strongest winds, are most likely to be over N Lynn Canal
and Clarence Strait. Those areas could see winds increase to 15 to
20 kts. Winds and seas will then diminish once again Thursday.

Outside (Gulf and Coastal Waters): An area of low pressure remains
just west of Baranof Island slowly moving southeasterly. Due to this
low, areas from Baranof Island southward will continue to see south
to southwesterly winds around 20 kts into this evening. There
continues to be a slight chance of thunderstorms along the coast,
south of Baranof Island into tonight. The main impact from any
thunderstorm development will be gusty winds. There may also be a
few lightning strikes possible. Later winds will then begin to
diminish into Wednesday. The next front will then move across the
gulf Wednesday afternoon and evening. This will once again increase
winds to around 20 kts from the southeast. We may see some of these
increased winds last into Thursday before a broad ridge enters the
gulf decreasing winds. This ridge will also change wind direction to
become more northwesterly.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Small Craft Advisory for PKZ011>013-021-031.

&&

$$

SHORT TERM...Bezenek
LONG TERM...Contino
AVIATION...NC
MARINE...EAB

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