Knik Fairview, Alaska 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

560
FXAK68 PAFC 200025
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
425 PM AKDT Tue May 19 2026

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

There is no end in sight for this very active pattern, so expect
continued cloud cover, cooler than normal temperatures, and
generally wet conditions - especially considering this is
typically one of the driest times of year. Starting with the
current analysis, a long-wave trough encompasses all of the Bering
Sea/Aleutians and extends eastward to mainland AK/extends across
the Bering Sea. A deep low which had served as the anchor of the
trough in the Bering has dissipated, but a new deepening low along
the western Aleutians is moving right in and will ultimately take
the place of the original low. A short-wave ridge over the
northeast Pacific is amplifying ahead of a digging short-wave.
This is steering the short-wave crossing the north Pacific
northward toward mainland AK. A surface low has formed ahead of
this short-wave and is tracking northward toward the Gulf.
Meanwhile, a short-wave is tracking northward across Southcentral
and beginning to exit to the Interior. This is producing some
showers inland and steady rain along the coast (mainly from Valdez
to Cordova). Southeasterly gap winds have weakened from their
peak, but persist for Turnagain Arm into Anchorage, the Knik River
Valley into Palmer, and along the Copper River. While the day
started out cloudy, breaks of sun are developing behind the short-
wave this afternoon.

The aforementioned north Pacific short-wave and surface low will
lift northward into the Gulf tonight. The short-wave will amplify
and become negatively tilted, with the strongest portion of the
trough crossing Prince William Sound and the Copper River Basin on
Wednesday. Have increased rainfall totals, with an inch or more
likely for Prince William Sound communities and around a quarter
of an inch for much of the Copper Valley. Models are in much
better agreement on spreading light rain north and west to the
western Kenai, Anchorage, and Mat-Su by early Wednesday morning.
Thus, have adjusted the latest forecast to indicate the likelihood
of light rain Wednesday morning. The main wind impact will be the
development of a barrier jet along the north Gulf coast ahead of
the surface low on Wednesday. Gale force winds are likely from
south of Cordova eastward to Cape Suckling. The upper short-wave
will exit quickly northward late Wednesday. Cooler air aloft
behind the trough combined with some breaks of sun will trigger
a few afternoon/evening showers.

There will be very little break before the new Bering storm begins
to affect Kodiak, the Gulf waters, and Southcentral. A leading
frontal system will cross the western Gulf Thursday while a series
of generally weak upper level short-waves stream northward across
Southcentral. There will be a big difference in the mean flow of
this storm system, with much deeper south to south-west flow as
you head up in the atmosphere. There will still be southeasterly
gap winds at the surface, but these winds will be much shallower
and downslope flow will be much weaker. As a result, expect much
more widespread rain and rain showers with this storm Thursday
through Friday - including the western Kenai, Anchorage, and the
Matanuska Valley. With weaker short-waves, rainfall along coastal
areas will be somewhat lighter than it has been in recent storms.
The Copper Valley will be notably drier than the rest of
Southcentral under this flow. Temperatures will remain below
normal under mostly cloudy skies.

-SEB

&&


.SHORT TERM FORECAST SOUTHWEST ALASKA, THE BERING SEA/ALEUTIANS
(Days 1 through 3)...

The deep upper-level trough and vertically stacked low over the
Bering continues to be the dominant weather feature and driver of
the overall weather pattern for much of the region. Early this
afternoon, isolated thunderstorms will be possible for northern
Southwest Alaska, from Bethel to Aniak and east. By this evening,
a shortwave pushing inland from the eastern Bering Sea will bring
a round of rainfall to the Kuskokwim Delta lasting through
tonight.

Beginning tonight, a new low pressure system, originating from the
northern Pacific will approach the western Aleutians, pushing a
swath of rainfall and gusty southeasterly winds from Adak to
Shemya early this evening. The low will continue to progress
northeastward, with the low center moving over Adak by Wednesday
afternoon, and its eastern leading front moving over Unalaska and
the Pribilofs. As its front tracks east, expect strong southerly
winds along the warm front, with the potential for westerly storm-
force gusts wrapping underneath the low, south of the Chain. The
front will then reach the Southwest coast by Wednesday night with
the front and parent low continuing to track northeast and
weakening through Thursday.

-CL

&&

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

Broad upper level troughing over the Bering Sea and Gulf looks to
continue to remain in place through the long term. Several
shortwaves rotating around the upper low across the western
Bering, North Pacific, and into the Gulf will continue to support
the active pattern and unsettled conditions across much of
southern Alaska through this weekend into early next week.

Models are in good agreement to begin the long term period with
widespread showers across the southern Mainland as a shortwave
lifts north out of the Gulf. Farther south, a more potent
shortwave and surface low tracks across the southern Gulf with
most of its moisture and energy directed towards the Panhandle. By
early next week, the upper low over the Bering Sea weakens in
favor of a new, stronger low lifting north out of the North
Pacific towards the Aleutians. Some uncertainty remains on the
speed and exact track the deepening surface low takes as it
approaches the Aleutian Chain, but all guidance eventually ends up
tracking this system into the southeastern Bering Sea by late in
the period. Gusty winds accompanied by light to moderate rainfall
can be expected along the Aleutians and Alaska Peninsula before
pushing into the Gulf, with the heaviest precipitation expected
along the southern AKPen and immediate Gulf coast.

&&


.AVIATION...

PANC...VFR conditions will persist. The gusty southeasterly winds
are expected to diminish late this evening and then become light
from the north after midnight. While south-southeast winds develop
again Wednesday afternoon, they should not be nearly as strong as
the past two days. Light rain is expected to develop late tonight
and persist on-and-off into Wednesday afternoon.

&&


$$