114
FXAK68 PAFC 280042
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
442 PM AKDT Thu Jun 27 2024

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

An upper level trough is draped across the western Gulf with a
developing low to the south. Kodiak has had rainfall this morning
and has since switched over to foggy conditions. Probability for
precipitation will gradually diminish through Friday morning and
the low shifts east, but the lower visibility and ceilings could
linger just a bit longer. For the rest of Southcentral,
predominantly southerly flow will persist over the next few days
as a ridge of high pressure remains blocked and in place across
the interior. Isolated to scatter thunderstorms have already
developed across the Talkeetnas, Alaska Range, and Wrangells this
afternoon with daytime heating. Temperatures have been warm and
dry for much of the Copper River Basin. Southerly flow through the
Copper River Valley could decrease RHs briefly this evening.
Folks should check on their local burn bans before burning and be
more aware of activities that could start a fire.

Those thunderstorms will decrease overnight as temperatures cool,
but for tomorrow afternoon and Saturday afternoon, storm
potential will become more isolated. Saturday afternoon,
thunderstorms will likely be confined to the northern Wrangells
and the eastern Alaska Range near the Tok Cutoff Road.

Models are hinting towards the idea that the low skirting south
and eastward of the Gulf will begin lifting north and sort of
retrogrades back into the northern Gulf by Sunday. This will bring
a shift to the overall weather pattern across Southcentral
Sunday. Light, stratiform precipitation is possible along the
northern Gulf and Prince William Sound coastlines with the highest
chances towards the Kenai Peninsula coast. About a tenth of
precipitation is expected at this time. Given southeasterly flow,
Anchorage and western Kenai Peninsula could be mostly downsloped.
Farther inland, pop up showers will be more likely than
stratiform, however, there will be a higher influx of moisture and
more widespread scattered precipitation can be expected. The
associated front from the Bering low appears to remain situated
near the western Gulf to some varying degree of strength that will
help keep weather cooler and moist near Kodiak through the short
term and by Saturday night, the front will likely bring Kodiak
about a quarter inch of rainfall through Sunday night, with a 40
to 50 percent chance of around half inch is possible.

rux

&&

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

The forecast remains on track for the Southwest coast to remain
cooler, unsettled, and showery the next few days with warmer and
relatively drier conditions for the interior locations. The
interior, especially along the Western Alaska Range, eastern
portions of the Lower Kuskokwim Valley, and along the Aleutian
Range in interior Bristol Bay, have the chance at afternoon
showers for the next few days. The best chance will be Friday
afternoon. However, the chances for lightning strikes are very
low at this time as the air should be more stable than it has been
the previous few afternoons across interior Southwest.

The central Bering Sea low will continue pushing waves of
moisture into coastal Southwest through Friday, which will help
to keep rain chances going. This low will eventually pivot back
towards the northwest Bering by Saturday. A North Pacific low and
upper shortwave are then expected to track along the Aleutian
Chain on Friday before stalling over the eastern Aleutians/Bering
and Alaska Peninsula from late Friday through Sunday. This will
aid in focusing precipitation along the Aleutian Chain and
southern Alaska Peninsula for Friday through Saturday evening
before it becomes more scattered and showery Sunday morning. Much
of the central Bering/Aleutians can also expect to see rain with
this system. By the end of Sunday, a high pressure ridge begins to
build across the Bering, tapering off any lingering precipitation
from west to east.

-Fenrich/DN

&&

.LONG TERM FORECAST (Days 4 through 7)...

A ridge of high pressure begins to break down through the weekend
as a front crosses the AK Pen and into Southcentral.
Southeasterly to southerly flow ahead of this front will bring
above seasonal temperatures to Kodiak and portions of the Kenai
Peninsula. Ridging continues to build in the Copper River basin
through the weekend. Toward the beginning of next week, model
discrepancy increases. Most models depict the Copper River Basin
high drifting southward and the building of a ridge westward
across the Prince William Sound toward Southwest Alaska. Others
hint at a series of lows moving into the Alaska Peninsula and
northern Gulf of Alaska thus keeping the aforementioned ridge from
migrating westward.

&&

.AVIATION...

PANC...VFR conditions and light winds will persist with light
southwesterly up-inlet flow prevailing into Friday. Building high
pressure over the area will also result in decreased precipitation
chances over the terminal.

BL/CC

&&


$$