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.

&&


$$