910
FXAK68 PAFC 151328
AFDAFC
Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
528 AM AKDT Sat Aug 15 2026
.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3)...
The pattern change is underway as the upper level ridge that has
been the source of the warm and often sunny weather the past few
days is moving eastward in response to a large upper level trough
digging into the Bering Sea and merging with a low south of the
Aleutians. Therefore expect cloud cover to increase today across
Southcentral. There remains a chance for a thunderstorm this
afternoon into early evening for the northern Susitna Valley and
northern Copper Basin. However, thunderstorm activity is expected
to be less than yesterday.
The big change gets going tonight as the front associated with
the Bering Sea low will move across Kodiak and then up Cook Inlet.
This front will bring more rainfall into Kodiak Island by this
evening and then coastal Southcentral tonight with the rain
spreading into more protected areas such as Anchorage and the
Susitna Valley on Sunday. The Copper River Basin will remain drier
due to downsloping from the strong southerly winds.
On Monday, the upper level flow will turn more southwesterly due
to the main upper level low pushing into Southwest Alaska. This
will bring more rainfall especially to the Susitna and Matanuska
Valleys and probably Anchorage and the northern Kenai Peninsula
as well. The gusty gap winds will likely persist through Monday as
this pattern is favorable for them for Turnagain Arm, Knik River
Valley an along the Copper River.
&&
.SHORT TERM FORECAST SOUTHWEST ALASKA/BERING SEA/ALEUTIANS
(Days 1 through 3: Saturday through Tuesday)...
A transition toward cooler and wetter pattern is underway across
Southwest Alaska as the upper-level pattern becomes increasingly
dominated by a deep low moving out of the North Pacific. Any
lingering showers across the Southwest Mainland today will become
increasingly tied to shortwaves lifting northward ahead of the
main system. Thunderstorm potential will continue to decrease as
cooler, more stable air begins to move into the region.
The main upper-level low lifts northward toward the Alaska
Peninsula and Southwest Alaska through Sunday. Numerous shortwaves
rotating around the low will move across the AKPEN and SOuthwest
Mainland, supporting periods of rain. Rain will increase across
the AKPEN first before spreading northward into Bristol Bay and
the Kuskokwim Delta. Rain becomes more widespread across Southwest
Alaska Sunday, with periods of moderate to locally heavy rainfall
possible as stronger shortwaves rotate around the upper low.
By Sunday night into Monday, the upper low moves farther into
Southwest ALaska while gradually becoming broader and more
elongated. additional shortwaves rotating around the circulation
will maintain periods of rain and showers across much of the
Southwest Mainland. The most persistent rainfall will gradually
shift north and east with the upper-level circulation, while
precipitation becomes increasingly showery farther south and west.
Cooler temperatures will accompany the system, marking a return to
a more typical cool and wet August pattern.
Across the Aleutians and Bering Sea, unsettled conditions will
continue as the North Pacific system tracks northward. Rain and
gusty winds spread across the eastern Aleutians and AKPEN before
conditions gradually become more showery behind the system.
Farther west, another weak disturbance moving out of the western
Bering may bring additional showers to portions of the central and
western Aleutians late in the period.
Model guidance remains in relatively good agreement with the
overall evolution of the upper-level pattern through Monday,
though differences remain in the exact position and strength of
individual shortwaves rotating around the main low. These
differences will influence the timing and location of the heaviest
periods of rainfall across Southwest Alaska.
LM
&&
.LONG TERM FORECAST (Days 4 through 7: Tuesday through Friday)...
By Tuesday morning, there is general agreement of a vertically
stacked low being over the Lower Yukon Valley. Troughing extends
down through the Aleutians, with the most significant shortwave
outside of the low being over the western Aleutian Chain. Models
hint at shortwaves continuing to rotate around the low as it
continues northward into the Interior. This will maintain chances
for precipitation for much of the southern Mainland Tuesday.
Specific timing of these waves is unknown, but the heaviest
precipitation is expected to fall along coastal regions of the
Northern Gulf Coast/Prince William Sound and along the Alaska
Range in the western Susitna Valley. Out west, the Aleutians and
Bering likely see showers Tuesday as the shortwave moves east.
The shortwave over the western Aleutians becomes a closed low over
the eastern Aleutians by Tuesday evening. This looks to pull
additional moisture in and bring another round of rain for the
eastern Aleutians, Southern AKPen, and Kodiak Island Tuesday night
through Wednesday. This low crosses the southern AKPen into the
Gulf Wednesday morning and moves into the Alaska Panhandle on
Thursday. As the low moves through the Gulf on Wednesday,
rainfall will likely shift to the northern Gulf Coast east of
Prince William Sound with some spilling over into interior
locations of Southcentral. Models diverge with resolving certain
surface features (mainly whether or not a surface low develops in
the Gulf on Wednesday). If a surface low develops in the Gulf
Wednesday, rainfall may be enhanced along the northern Gulf coast.
Some southeast gap winds (Turnagain, Knik, and Copper River
winds) may be enhanced as well on Wednesday. These details will
become more clear in the coming days.
To the west of the lows, models diverge on solutions between
zonal flow and attempts at a ridge building in the Bering with
additional shortwaves traversing into the southern Mainland.
Either pattern would support cooler temperatures and mostly overcast
skies across much of southern Alaska and the Bering with
continued chances for precipitation across the southern Mainland.
-PA
&&
.AVIATION...
PANC...VFR conditions will persist through the period, though
ceilings may lower to under 5000 ft starting this afternoon with
an approaching frontal system. This system will bring rain to the
area overnight, though there is a question as to how much will
make it to the terminal in the cross-barrier flow over the Chugach
Mountains. The best chance for rain and a MVFR ceiling will be
late tonight into early Sunday morning.
Winds should remain southerly to westerly today into tonight but
remain at or under 10 kt through Sunday morning.
&&
$$
489
FXAK69 PAFG 151436
AFDAFG
Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
636 AM AKDT Sat Aug 15 2026
.KEY MESSAGES...
Central and Eastern Interior...
- Warm conditions peak Saturday and Sunday, with valley high
temperatures ranging between the mid 70s and lower 80s.
Temperatures cool to below 70 degrees beginning Monday.
- Dry conditions prevail Saturday, though isolated thunderstorms
are possible south of Fairbanks. Widespread showers return
beginning early next week.
- A Wind Advisory is in effect for the Eastern Alaska Range from
10 AM Sunday through 12 AM Tuesday for gap winds gusting to 55
mph through Isabel Pass.
West Coast and Western Interior...
- Warm temperatures continue Saturday, with inland highs
reaching the mid to upper 70s and coastal areas in the 60s to
near 70. A Heat Advisory is in effect from 5 AM to 8 PM AKDT
Saturday for the Noatak and Lower Kobuk Valleys and the Seward
Peninsula for temperatures reaching 75 to 80 degrees.
- Isolated to scattered thunderstorms are possible in the Lower
Yukon Delta area Saturday afternoon. Substantial moisture
brings moderate to heavy rainfall potential to the southwest
coast and inland areas Sunday night into Monday.
- The overall pattern shifts late Sunday into Monday as a low
pressure system moves inland, cooling temperatures and
bringing elevated precipitation chances through midweek.
North Slope and Brooks Range...
- Warm conditions continue across the northern slopes of the
Brooks Range and Arctic Plains through Sunday, with highs
reaching the 60s and 70s, approaching 80 near Umiat. Onshore
easterly winds keep the Eastern Arctic Coast cooler, with
highs in the 50s.
- Mostly dry conditions prevail Saturday and Sunday before rain
chances return by Monday.
&&
.SYNOPSIS...
Warm conditions will prevail through the weekend across
Northern Alaska before cooler and wetter weather takes over by
early next week. A persistent ridge will keep the Interior and
North Slope mostly clear and dry through Saturday, though a
passing shortwave will trigger isolated to scattered afternoon
thunderstorms from the Southwestern Interior through the
Central and Eastern Interior. On Sunday, a pattern shift begins
as a Bering Sea low advances inland, driving the ridge eastward
and pushing a surface front across the Alaska Range. This system
will bring gusty gap winds through mountain passes, cooler
temperatures, and widespread rainfall that will persist across
the state through much of next week.
&&
.SHORT TERM /THROUGH SUNDAY NIGHT/...
The 576 decameter ridge entrenched over the Interior will
dictate the region`s weather through Saturday night. This
feature continues to deflect systems away from the region while
maintaining widespread clearing. Beneath the high pressure dome,
850 mb temperatures reaching 11-14C will support high
temperatures in the mid to upper 70s, with some locations
approaching the lower 80s. The peak warmth will concentrate
across the Central and Eastern Interior, as well as areas
directly north of the Alaska Range, though highs in the 70s will
extend into the Western Interior and parts of the North Slope.
The potential for high temperatures to reach 75 to 80 degrees
has prompted a Heat Advisory from 5 AM to 8 PM AKDT Saturday for
the Noatak and Lower Kobuk Valleys, as well as interior
portions of the Seward Peninsula.
A shortwave tracking around the outer margin of the ridge will
bring chances for isolated thunderstorms Saturday afternoon.
This activity will focus across an arc stretching from the
southern half of the Western Interior south of the Seward
Peninsula through through the southern half of the Central and
Eastern Interior.
A pronounced synoptic transition unfolds on Sunday, marking a
shift toward cooler and wetter conditions for Northern Alaska.
Aloft, the ridge that has dominated the pattern will be nudged
eastward into the Yukon as low pressure takes over. An initial
shortwave rotating around a stronger low toward the Kuskokwim
Delta will be quickly overtaken by the low itself Sunday into
Monday. This primary low will completely dislodge the remnant
ridge, directing a plume of deep moisture into the Western
Interior alongside an organized cold front advancing across the
Alaska Range. Expect widespread rainfall and strengthening winds
to spread into the Central and Eastern Interior by Sunday night
into early Monday morning. A Wind Advisory is in effect for the
Eastern Alaska Range North of Trims Camp from 10 AM Sunday to 12
AM AKDT Tuesday for southerly winds of 25 to 35 mph with gusts
up to 55 mph. Overall rainfall totals through Tuesday will range
from 0.5 to 1.5 inches across the Western Interior, with
lighter amounts expected farther north and east.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
Broad troughing and cool, unsettled weather will prevail across
Northern Alaska throughout the extended forecast period as the
stagnant blocking pattern breaks down. High temperatures will
drop significantly, broadly dropping below 70 degrees across the
region from Tuesday onward as the upper ridge axis shifts
eastward into the Yukon and Northwest Territories. Aloft, model
consensus shows reasonable agreement regarding the primary
trough progressing eastward, though uncertainty remains mid to
late week concerning the timing and track of a secondary low
developing upstream over the Bering Sea.
A low pressure system in the eastern Bering Sea will maintain
strong southerly flow through the Alaska Range on Monday, with
winds gusting up to 55 mph possible through Isabel Pass before
easing on Tuesday morning. Southerly winds will direct a plume
of deep moisture into Western Alaska, bringing widespread
rainfall to the Western Interior and the Alaska and Brooks
Ranges. The wettest locations, particularly in the Southwestern
Interior and Western Brooks Range, could see localized rainfall
accumulations exceeding one inch on Monday. From Tuesday onward,
precipitation across the Interior and North Slope will become
more scattered as the principal low moves inland and weakens.
While the potential for heavy rainfall diminishes mid to late
week, periods of showers will persist across the region.
Temperatures will remain near normal though the remainder of the
forecast period.
Coastal Hazard Potential...
No coastal hazard concerns are expected.
&&
.FIRE WEATHER...
At the start of the weekend, fairly warm and dry weather continues
over most of Northern Alaska as upper level ridging remains over the
state. A shortwave feature embedded in the overall flow has moved
south over the Central/Eastern Interior early Saturday morning,
which is working to support scattered showers and a few isolated
thunderstorms across the region. Precipitation amounts from Friday
generally ranged from T-0.10" with locally higher amounts closer to
0.50" at higher elevations. A similar trend is expected through
Saturday afternoon as the shortwave feature pushes farther south
towards the Alaska Range. Along with this feature, another pre-
frontal system in the Gulf of Alaska lifts north into the YK Delta
Saturday afternoon, fueling additional isolated to scattered showers
and thunderstorms across Southwest Alaska into Sunday. The highest
thunderstorm activity will likely be from the Upper Kuskokwim Valley
towards the Nulato Hills. Naturally, cooler temperatures and higher
min RHs will be expected where the most active weather develops.
Elsewhere, high temperatures will rise back into the upper 70s/low
80s, especially in the Yukon Flats, Upper Tanana Valley, and Arctic
Plains. For coastal regions, temperatures will continue to be a bit
more mild in the mid to upper 60s. As for min RHs, they should
generally fall between 30-40% with isolated areas seeing below 30%
possible Sunday afternoon.
Looking towards Sunday, a more dramatic change in the pattern starts
to take shape as a low tracks northeast across the Alaska Peninsula
and into Bristol Bay Sunday morning/afternoon. As this low
approaches the state, a brief period of southerly flow sets up over
the Alaska Range yielding the potential for southerly gap winds
through the passes. A Wind Advisory is in effect Sunday morning
through late Sunday night for winds gusting up to 55 mph expected.
In addition to gusty winds, this system brings with it quite a bit
of moisture from the Gulf and is expected to bring widespread
showers to much of Northern Alaska, including portions of the
Central/Eastern Interior. A few isolated thunderstorms may develop
ahead of any frontal boundary that develops, but activity should be
fairly limited for the most part. By early next week, temperatures
will cool to around seasonable norms with plenty of rain and cloud
cover to usher in more fall-like weather.
&&
.HYDROLOGY...
Expect water levels to rise on rivers throughout the Kuskokwim
Delta and Western Interior as 0.5 to 2.0 inches of rain falls
from Sunday night into Tuesday. Rivers are expected to remain
within their banks, and no flooding is expected.
&&
.AFG WATCHES/WARNINGS/ADVISORIES...
AK...Heat Advisory from 5 AM to 7 PM AKDT Saturday for AKZ814-816-
818-823.
Wind Advisory from 10 AM Sunday to 7 PM AKDT Monday for AKZ849.
MARINE...Small Craft Advisory until 4 AM AKDT Saturday for PKZ857.
Small Craft Advisory until 4 AM AKDT Saturday for PKZ858.
&&
$$
KEY MESSAGES...Satcher
SYNOPSIS...Satcher
SHORT TERM...Satcher
LONG TERM...Satcher
FIRE WEATHER...Santiago
415
FXAK67 PAJK 151343
AFDAJK
Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
543 AM AKDT Sat Aug 15 2026
.SYNOPSIS...
Key Messages:
- Quiet weather continues for the first half of the weekend before
cooler weather returns for the second half of the weekend.
- A pattern change looks to arrive Monday as rain chances return
from north to south. Chances for wetting rains increase
significantly for next week.
&&
.SHORT TERM...A ridge of high pressure in the gulf will continue
to keep conditions relatively warm and dry over southeast Alaska
this Saturday. Multiple areas including Prince of Wales Island as
well as the Borough of Haines including Klukwan will likely see
temperatures reach around 80 degrees again this afternoon. This
high pressure also helped support a marine layer developing
overnight, with significant visibility reductions at times in near
coastal waters including filtering into Cross Sound, as well as
the northeast gulf coast. This marine deck is expected to rise and
thin out with daytime heating through the morning hours. However,
the ridge will stay around long enough for this marine layer to
likely reform overnight and bring similar adverse conditions to
the same areas Sunday morning.
A low moving into the Alaska peninsula will gradually push a front
across the gulf on Sunday, displacing high pressure over the
region. This will bring about a pattern change of increasing cloud
cover, increasing southerly winds and onshore flow, as well as
relatively cooler temperatures and increasing rain chances.
Moderate rain is expected to impact the northern coast by Sunday
night, with light to potentially moderate rain showers expected
to spread eastward into the inner channels late Sunday into
Monday. For more information on this, see the long term discussion
below.
.LONG TERM...A couple of interesting features for Southeast
Alaska for the next work week as the ridge plaguing the area
finally breaks down fully on Monday. An upper level low moving up
from the Aleutian Chain looks to swing across a negatively tilted
shortwave across the northern gulf. The warm sector and warm front
associated with this trough looks to move into the northern half
of the panhandle first, raising snow levels briefly to well over
10000 ft and inviting warm rain processes. This combined with
orographic lifting will result in the heaviest portion of
rainfall, with Yakutat having a 80% likelihood of exceeding 1.5
inches of rain overnight on Monday. As the warm front weakens and
becomes occluded, rainfall drops rather dramatically to less than
a half inch during the latter portion of Monday. Winds are
expected to roughly follow the same story, with a barrier jet
forming along the NE gulf coast, with up to gale force winds
between Icy Cape and Cape Suckling, and strong southeasterlies
elsewhere.
As the southwesterly energy surges over the Coast mountains,
expecting to see some leeside troughing which, in combination with
the continued ridge axis in the southern panhandle, will cause a
significant southerly pressure gradient. Its during this time
(Monday) that moderate to strong southerly breezes for Chatham
Strait, Stephens Passage, and Lynn Canal will begin, with Skagway
possibly exceeding 40 mph gusts.
Beyond Monday, the active pattern continues, but confidence on
individual features drop from moderately high to moderately low.
Even still, confidence is increasing that another system may be in
the works for Wednesday, bringing more rain and wind.
&&
.AVIATION...VFR conditions prevail across most of the panhandle
this morning. The exceptions are along the outer coast and into
Cross Sound where marine layer low clouds (and some fog) has moved
in overnight creating areas of IFR or lower conditions. Those
marine layer clouds are expected to remain mostly along or just
offshore of the outer coast today before starting an inland push
tonight. Clouds with MVFR or IFR ceilings will likely reach up Icy
Strait to Gustavus or Hoonah, up Peril Strait, and into Craig and
Klawock by late tonight. May also have some clouds reaching up
southern Clarence Strait into Ketchikan and Metlakatla as well.
Other then that the only other concerns are afternoon sea breezes
that may be up to 15 kt in some locations.
&&
.MARINE...
Inside water...Still a mostly quiet marine forecast for the next
few days. Mostly lighter winds with afternoon sea breezes being
the main driver of any higher winds. Marine layer low clouds and
fog will likely be encountered near ocean entrances and Cross
Sound today which may extend into Icy Strait, Peril Strait, and
southern Clarence late Sat night and Sunday morning. Change starts
to come for Monday as a new front moves in from the west bringing
some breezy conditions (up to 15 to 25 kt) and precipitation for
the northern inner channels and Yakutat Bay.
Gulf Waters: One more quiet day for the gulf before a new front
begins to move in on Sunday and Sunday night. Winds are currently
mostly NW at 15 kt or less with 5 ft or less seas. Some areas of
low clouds and fog are present along the outer coast this morning
bringing some reduced visibilities to some areas and will likely
persist into Sunday. The new front will bring SE winds to 20 to
30 kt mainly for the northern and central gulf Sunday night before
winds switch to westerly post front and diminish to 10 to 20 kt
on Monday. Sea likewise will be building Sunday night into Monday
up to around 9 ft before slowly starting to subside there after.
This will be first accomplished by winds building wind wave Sunday
night followed by a 5 to 6 ft SW swell moving into the area on
Monday.
&&
.FIRE WEATHER...
&&
.HYDROLOGY...
&&
.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Heat Advisory from 10 AM this morning to 7 PM AKDT this evening
for AKZ319-328.
MARINE...Small Craft Advisory for PKZ651-652-663-664-671-672.
&&
$$
SHORT TERM...STJ
LONG TERM...NC
AVIATION...EAL
MARINE...EAL
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