505
FXAK68 PAFC 061310
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
510 AM AKDT Sun Jul 6 2025

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

Ridging over the North Slope will continue weakening as a low
moves into the Gulf of Alaska and its front stretches along the
north Gulf coast with various shortwaves rotating northward into
Southcentral. Cloud cover will continue to increase, becoming
mostly cloudy to overcast over the next couple of days, and rain
will become a prominent feature along the coastal regions and
likely a large portion of the Copper River Basin. There is a
chance for light rain in Anchorage and the Mat-Su Valleys on
Monday, though some uncertainty remains. Rain is also expected
along the eastern portions of the Kenai Peninsula. With persistent
easterly flow it is possible rain showers will spill over into
the eastern portions and over Cook Inlet on Monday.

&&

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

A rex block remains in place over the Alaskan mainland. This is
funneling shortwaves from over the interior and across Southwest
this morning. Thunderstorms have been observed overnight in the
Kuskokwim River valley, which will likely remain north of Bethel.
The strongest convective indicators appear to remain closer to
McGrath and Russian Mission. There is higher confidence that this
system will deliver stratiform wetting rains to portions of
Southwest, with totals of 0.25 to 0.50 inch expected from Stony
River to Aniak, and from Bethel to Togiak. Higher amounts up to
1.20 inches may be possible for the Kilbuck and Ahklun Mountains.
Following the departure of this shortwave, drier weather is lined
up for the Southwest Mainland Monday and Tuesday.

Meanwhile, a North Pacific low south of Amchitka will push gusty
winds and moderate rainfall ahead of it as it tracks eastward
along the chain. Small craft winds may be possible across portions
of Bristol Bay for mid-week.

&&

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

The long-term period begins with a shortwave ridge over
Southcentral Alaska, weak flow across Southwest Alaska, and a
North Pacific low south of the Eastern Aleutians and southern
Alaska Peninsula (AKPEN). The ridge over Southcentral Wednesday
looks to move northward and reorient with a more east to west axis
across the central interior by Thursday. This will open the door
for the North Pacific low to move into the Gulf of Alaska by
Thursday. Wettest locations look to be across Kodiak Island, the
Eastern Kenai Peninsula, and Prince William Sound with scattered
showers for Southwest and interior Southcentral. Steady rains
across the Southcentral coast taper off to a more showery regime
Friday and Saturday very much like inland locations as the low
weakens and energy goes to Southeast Alaska.

Further to the west, an upper level shortwave looks to dig
southward from northern Kamchatka into the central Bering by
Thursday. Rain looks to be mostly confined to the Bering but may
make it as far south as the Pribilof Islands and as far east as
Nunivak Island. Elsewhere, a ridge across the western Bering will
weaken into Thursday and allow for a few weak systems tracking
southeastward from southern Kamchatka to move over the Western
Aleutians and Bering by Friday. Rain with these systems will be
light. The ridge looks to build back across the western Bering by
Saturday. Confidence remains low and uncertainty remains high
regarding the track of a North Pacific low Thursday through
Saturday. Some guidance keeps the low south of the Aleutian Chain
(Canadian and somewhat the ECMWF) while some guidance wants to
clip the Central/Eastern Aleutians and southern AKPEN with the
front bringing another round of light rain to those areas.

&&

.AVIATION...

PANC...VFR conditions will persist through tonight. Winds become
southeasterly and gusty later this afternoon. Isolated to
scattered showers along the Chugach Mountains this afternoon and
evening could move into the vicinity of the terminal.

By Monday morning, a wave of energy will likely bring steady rain
over the terminal through much of the day, with ceilings dropping
below 5000 ft and as low as MVFR. There remains uncertainty with
this feature as Anchorage sits on the western edge of where the
band of rain is expected to develop, and there are some minor
differences in timing with the wave.

&&


$$