426
FXAK68 PAFC 190039
AFDAFC
Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
439 PM AKDT Fri Jul 18 2025
.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through
3: Tonight through Monday)...
The last vestiges of rain showers associated with a weakening low
in the Gulf, east of Kodiak, are pushing into Prince William Sound
this evening. Upper level support continues to run out ahead of
the low, which will cause shower coverage to continue to diminish
and prevent much northward spread of precipitation. Inland
locations are not expected to see anything from this feature. A
weak coastal ridge and partly cloudy skies have allowed light
southerly gap flow to develop for the Copper River Valley and
Turnagain Arm. These winds diminish tonight.
Heading into the weekend, a ridge of high pressure amplifying in
the North Pacific builds north, putting the southern Mainland on
its northern periphery. This will allow generally warm and dry
conditions to persist. However, a series of weak shortwaves that
eject from a large Bering Sea low and ride over top the ridge
axis, threatening to bring periods of light rain at times for
mainly the western half of Southcentral. There is a slight chance
on Saturday for a weakening Bering front to bring light rain to
the area, but Sunday looks to have better chances. The most
favored area for up to around a tenth of an inch or two would be
the western Kenai Peninsula, with, much like the past two
disturbances, precipitation chances and amounts decrease to the
north and east into Anchorage and the Mat-Su Valleys. With any
rain expected to be fairly light, expect valley temperatures to
be quite warm Saturday through Monday, with much of Anchorage and
the Mat-Su Valleys approaching 70F for highs. Parts of the Copper
Basin will approach 80 degrees each afternoon as well. For Monday,
southern portions of the region look to remain dry, while
continued weak shortwaves riding over the ridge may induce shower
activity closer to the Alaska Range. Building surface high
pressure over Southwest Alaska will induce strengthening westerly
winds out of gaps and across the Gulf of Alaska.
&&
.SHORT TERM FORECAST SOUTHWEST ALASKA/BERING SEA/ALEUTIANS
(Days 1 through 3: Today through Sunday)...
The persistently stationary Bering Sea low begins to move slowly
eastward this weekend as high pressure in the North Pacific Ocean
builds. Cloudy, foggy and rainy conditions continue through the
weekend.
A front moving through the Alaska Peninsula and into the
Southwest Mainland will continue to bring rain and southwesterly
winds to this region through tomorrow afternoon. Onshore winds
into the Bristol Bay coastline could reach small craft advisory
levels briefly this evening. Consistent model trends the past few
days remain so confidence is high for heavier rain showers to move
onshore from Dillingham and Aleknagik to Cape Newenham early
tomorrow morning. Onshore winds turn more southwesterly to
southerly causing rounds of afternoon showers to shift northward
along the coast from Cape Newenham to Toksook Bay. The southern
edge of these showers move through Bethel and Aniak in the late
afternoon hours. Simultaneously, tomorrow afternoon, a heavier
band of rain showers move through the Eastern Aleutians and
Alaska Peninsula. This includes Cold Bay, Kind Salmon and, late in
the afternoon, Iliamna. Behind these main waves of showers,
isolated rain, fog and cloudy skies will persist through Sunday.
&&
.LONG TERM FORECAST (Days 4 through 7: Tuesday through
Friday)...
By Tuesday, southern Alaska will be devoid of a significant low
pressure system, with the pattern largely driven by a strong ridge
of high pressure built over the northern Pacific. This pattern
may still work to keep showers across Southwest and Southcentral
Alaska with plenty of cloud cover as air continues to flow in from
the Bering Sea. Shortwaves coming up and over the ridge will
maintain the unsettled pattern along the Alaska Peninsula and into
Southwest/Southcentral mainland Alaska. Expect more widespread
stratus built across the Bering Sea given the influence from the
ridge.
-CL
&&
.AVIATION...
PANC... VFR conditions will persist. The light sea breeze from
early this afternoon is expected to give way to a southeasterly
Turnagain Arm late in the afternoon. This should bring in winds
with gusts of 15-20 kt this afternoon and evening, then diminish
overnight. Expect the westerly sea breeze to return for Saturday
afternoon.
&&
$$
731
FXAK69 PAFG 182230
AFDAFG
Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
230 PM AKDT Fri Jul 18 2025
.SYNOPSIS...A storm system will spread moisture in a southwest
flow aloft over the Interior for the next week. The western
Interior and west coast will receive occasional rain during this
time. The remainder of the Interior and Brooks Range will receive
scattered showers and isolated thunderstorms...until more
widespread rain moves up around next Wednesday and Thursday. Highs
will be in the 70s this weekend. The Arctic Coast remains colder
with gusty east winds and areas of fog Saturday...but warms into
the 50s again by Sunday.
&&
.KEY WEATHER MESSAGES...
Central and Eastern Interior...
- High temperatures mainly in the 70s with light winds through the
weekend. Skies will be partly cloudy.
- Scattered showers and isolated thunderstorms mainly over the
higher terrain this weekend.
West Coast and Western Interior...
- Occasional rain Saturday night and Sunday mainly west of a Huslia-
McGrath line. Scattered showers elsewhere.
- Winds mainly offshore and 15 mph or less along the coast through
Sunday. Gusty south-southwest winds on Monday.
- Temperatures remain steady for Saturday...60s near the west
coast...70s in the Interior. Temperatures cool Sunday and
Monday.
North Slope and Brooks Range...
- East winds 20 to 35 mph along the Arctic coast Saturday...
decreasing to 10 to 20 mph Sunday.
- Scattered showers and isolated thunderstorms mainly over the
Brooks Range this weekend.
- Gradual warming Sunday into Tuesday. Highs in the 50s and low
60s along the coast...with 70s possible in the Arctic Plain.
&&
.FORECAST ANALYSIS AND DISCUSSION...Shortwave energy in a
moist southwest flow aloft will trigger scattered showers and
isolated thunderstorms over the higher terrain of Interior the
next several days. Lightning activity is expected to be minimal
this evening but more than yesterday. Isolated thunderstorm
formation is favored over the Fortymile country and eastern
Alaskan Range. Storms will spread up into the Brooks Range this
weekend. More widespread light rain will occur roughly west of
Huslia-McGrath line later tonight into Sunday. High temperatures
this weekend will be in the 70s except for 60s along the west
coast with the clouds and rain. The Arctic Coast remains colder
with gusty east winds and areas of fog Saturday... but warms into
the 50s again by Sunday.
&&
.FIRE WEATHER...
Temperatures this weekend will remain slightly above normal, with
southwest flow on Saturday bringing stratiform rain over the West
Coast and Western Interior; chances for thunderstorms hang on
across parts of the Interior and even the North Slope. Southwest
flow looks to continue into next week, bringing more rainfall and
cooler temperatures into the Interior. RHs look to remain plenty
wet in these patterns, mainly above 40% with a few readings in the
30-40% range possible across the Upper Tanana Valley each day
through Sunday. Northeast winds will gust to 15 mph across the
Yukon Flats Friday afternoon through Sunday. Southerly gap winds
will gust to 30 mph through Alaska Range passes on Sunday.
&&
.HYDROLOGY...No concerns at this time. We will monitor potential
flash flooding from the day 3-7 hazardous rainfall projections by
WPC .
&&
EXTENDED FORECAST DAYS 4-7...There is good model agreement that a
low will move over the Bering Sea by Sunday...and then up near
the Bering Strait by next Tuesday. The high pressure ridge is
pushed east over the Canadian Yukon and breaks down. A series of
shortwaves will rotate around this low and move up over the
Interior in a moist west-southwest flow. Hazardous rainfall
remains possible on Tuesday over the Brooks Range...and along the
Denali Park Road and north side of the Alaska Range west of the
Parks Highway. Ensemble solutions want to move the Bering low
energy down over the Interior the middle of next week. The cold
frontal boundary forcing will result in widespread rainfall as it
tracks east. Hazardous rainfall will also be possible Wednesday
and Thursday over the eastern Alaska Range and Fortymile country.
This is a wet pattern that will likely settle down our wildfire
activity even more. Even the Yukon Flats could see some widespread
rain late next week.
Coastal Hazard Potential Days 3 and 4...None
&&
.EXTENDED FORECAST DAYS 4-7...
Coastal Hazard Potential Days 3 and 4...None
&&
.AFG WATCHES/WARNINGS/ADVISORIES...
AK...None.
PK...Small Craft Advisory for PKZ801-850-851.
Small Craft Advisory for PKZ802.
Small Craft Advisory for PKZ812-815-858.
Small Craft Advisory for PKZ813.
Small Craft Advisory for PKZ814.
Small Craft Advisory for PKZ816.
Brisk Wind Advisory for PKZ859.
Brisk Wind Advisory for PKZ860-861.
&&
$$
Maier/Park (FWX)
288
FXAK67 PAJK 182318
AFDAJK
Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
318 PM AKDT Fri Jul 18 2025
.SHORT TERM.../Through Saturday night/ Fairly quiet conditions
across the panhandle with dry weather and mostly mid level clouds
across a wide area of the panhandle (lots of sunny breaks around
Kuiu Island, Western Prince of Wales, Ketchikan, Annette Island,
and Misty Fjords). It is these clouds that have kept temperatures
in the upper 50s to low 60s for the most part this afternoon so
far while areas that are seeing some sun have temps reaching into
the mid to upper 60s. As of 1 pm, some breaks in the clouds are
starting to appear across the northern inner channels, but they
are being slow to develop.
Quiet conditions are expected to continue as ridging over the gulf
strengthens. The question is how long the cloud cover will stick
around. Wind streamlines suggest that flow will remain slightly
onshore into Cross Sound into Saturday at least so clouds around
Icy Strait, Peril Strait, and possibly further inland will stick
around into Saturday. However, low level flow looks to start to
turn just enough offshore by late Saturday that northern inner
channel areas may see more breaks in the cloud cover come Saturday
afternoon. This also means that expected high temperatures for
Saturday will be a little warmer then what was seen today. For the
southern panhandle flow is mostly offshore through the period so
more substantial breaks in the cloud cover is expected with
corresponding higher afternoon temps.
Winds are mostly 15 kt or less today and are expected to stay that
way. The only things that may break that pattern are the usual sea
breeze circulations that develop in the afternoons and evenings.
Especially if any substantial sunny breaks develop which could
produce some sea breezes up to 15 to 20 kt in localized areas.
.LONG TERM.../Sunday through Thursday/...A surface high pressure
system in the southern Gulf of Alaska continues to build through
the week, stalling over the southwestern gulf due to broad upper
level ridging. This ridging will funnel more dry air over the
panhandle, continuing the warming and drying trend into the long
term. Multiple approaching shortwaves in the gulf attempt to
strengthen through the weekend which could increase chances for
light precipitation along the northern gulf coast, though all look
to break apart before reaching the outer coast. The surface
ridging continues to strengthen into early next week which will
clear out skies and tighten the pressure gradient, increasing wind
speeds along the gulf coast. By Monday afternoon, sustained winds
will increase to 20 kts going into cross sound, with highest
speeds reaching around up to 30 kts off the southwestern coast of
PoW. Gusts may reach 30 kts in Dixon Entrance. A tightening
pressure gradient will bring up wind speeds from the northwestern
gulf, and an ESE direction is conducive to gap winds coming out
from between Kodiak Island and the Kenai Peninsula. From this, the
central gulf can expect to see up to 30 kts of westerly winds
with wave heights reaching 13 ft through Tuesday. The consistent
NW upper-level winds help to pull a deep upper-level trough down
over the panhandle Wednesday afternoon. This will assist the
associated surface shortwave trough in strengthening to a weak,
closed low over the northern gulf coast, bringing precipitation
back into the forecast for Thursday.
Clearing skies will allow for a sea breeze to develop in some of
the inner channels, with winds potentially reaching 10 to 15 kts
near the water in Juneau, Haines, and Skagway. Stronger winds are
expected through Icy Strait and up Lynn Canal with this sea
breeze, peaking in the mid afternoon. This is also conducive to
marine layer development along the gulf coast which will bring low
clouds to coastal regions and pushing into Cross Sound.
High temperatures of between 13 to 15 degrees C at 850 mb with
areas of 16 degrees C and clearing skies indicate warmer surface
temperatures for early next week, raising for Monday and peaking
Tuesday. Interior regions of the panhandle will experience the
highest temperatures, with highs potentially reaching the mid to
high 70s and lows in the mid 50s. Max temp EFI values have stayed
consistently high Monday through Wednesday. NBM probabilities are
indicating a 60% potential of reaching 80 degrees in areas of
Skagway and Haines and an 80% potential in Hyder on Tuesday. These
are areas of known temperature biases for the NBM and other
models are only estimating around a 30% chance just for Hyder, so
confidence is very low on temperatures actually breaching 80.
&&
.AVIATION...Mid level clouds across the panhandle and the gulf
coast waters. A ridge of high pressure over the gulf keeps an
onshore wind flow. The north Lynn Canal is a bit out more
scattered clouds. Most clouds this evening in the 3500 to 5000 ft
ceiling range. Likely will see them staying the same, or lowering
to 2500 to 3500 feet. Saturday the southern half the of the
panhandle should start to see breaks developing in the clouds.
&&
.MARINE...Inside waters: Wind conditions are rather low with 15 kt
or less observed in most areas, and with the exception of Lynn
Canal, wind directions are mainly N or W. Not much change expected
over the next few days in the inner channels with mainly N and W
flow with speeds of 15 kt or less and seas of 3 ft or less. The
main exceptions will be areas with strong sea breezes, like near
Skagway, and Cross Sound, where 20 kt winds could be seen during
the afternoons and early evenings.
Outside Water: W to NW flow is the main wind direction in the
gulf today and that is mainly expected to remain the case for the
next few days. Highest winds are around 15 kt off Prince of Wales
Island and in the central gulf. Combined seas are around 4 ft
with most of that being a 3 to 4 ft SW swell of 8 sec period.
These conditions are not expected to change all that much through
the weekend as ridging settles into the gulf. Highest winds
(around 15 to 20 kt) will mainly be off the western coast of
Prince of Wales Island through the period.
&&
.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...None.
&&
$$
SHORT TERM...EAL
LONG TERM....ZTK
AVIATION...Bezenek
MARINE...EAL
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