Area Forecast Discussion
Issued by NWS Anchorage, AK

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FXAK68 PAFC 161328

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
528 AM AKDT Sun Jun 16 2024

through Tuesday)...

The overall weather pattern is similar to yesterday with lots of
clear skies in the morning (except right along the north Gulf
coast of the eastern Kenai Peninsula) and warm temperatures
expected across the region. Afternoon showers and thunderstorms
are expected once again, but there are a few key differences from
yesterday in this area. The first is that yesterday`s
thunderstorms that developed over Anchorage and the Kenai
Peninsula were largely influenced by a very weak 500 mb low that
developed near the north Gulf coast and is northeast of Kodiak
Island as of this writing early Sunday morning. While this low was
weak, as was mentioned in yesterday morning`s forecast
discussion, it was enough to bring more organized thunderstorms
for these areas and is still producing some thunderstorms
northeast of Kodiak Island early this morning. Today will not have
this low so even though the atmosphere remain unstable, the
thunderstorm development should be more random in nature with
elevated heating over the mountains being a key trigger today. The
atmosphere over the Copper River Basin is not as unstable as
areas farther west, but there could still be a few isolated
thunderstorms n the area again today.

For Monday, temperatures will begin to cool a little across the
region, but still remain pleasantly warm. Thunderstorms for
Monday into Tuesday are more likely to be relegated to along the
Alaska Range with some showers over elevated terrain over the rest
of southcentral. Tuesday will also bring a pronounced change to
Kodiak Island as a front will move over the Island and bring rain
with it.


1 through 3)...

Upper level ridging shifts northwards as a series of shortwaves
move through Southwest Alaska over the next few days. Convective
activity is expected to produce some wet thunderstorms today and
Monday afternoon along the central/eastern portions of the Lower
Kuskokwim Valley and Bristol Bay as well as along the Western
Alaska Range. Thunderstorm activity becomes more widespread Monday
afternoon/evening potentially pushing further west into the
Kuskokwim Delta. Small craft winds near the Eastern Aleutians will
continue diminishing as the front over the area weakens through
today. Rain chances return to the Eastern Aleutians Monday as a
weak surface low spins south of the Aleutian Chain.


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

A broad upper-level low extending along and south of the Aleutian
Islands and Alaska Peninsula on Wednesday shifts eastward through
the end of the week. Rainy conditions associated with a weak front
shift from the Alaska Peninsula, Kodiak Island, and Bristol Bay
into the Gulf of Alaska for Thursday. A series of shortwave
troughs embedded in the broad upper low lift into southern
mainland Alaska and then rotate westward on Thursday and Friday,
bringing a slight cool down and wetter conditions. Increased lift
afforded by these shortwaves will lead to areas of more
widespread, steadier rainfall across portions of Southcentral and
Southwest Alaska. For Friday, a North Pacific low passes south of
the Gulf of Alaska, approaching Southeast Alaska/Haida Gwaii by
Saturday. The low pressure draws theta-e ridging southward from
Interior Alaska, allowing a return to warmer weather and
thunderstorm potential for the southern mainland next weekend.

Out west, surface high pressure over the Bering Sea will likely
support widespread fog and low stratus across the western and
central Bering on Wednesday and Thursday. A North Pacific low,
potentially gale-force, begins to push into the western/central
Aleutians for Friday, scouring out some of the fog, but bringing
windier, wetter conditions. Heading into the weekend, the low
progresses north and east, spreading rain and gusty southeasterly
winds potentially as far as the Alaska Peninsula.




PANC...VFR conditions and light winds will generally prevail
throughout the TAF period. The potential for showers and even a
thunderstorm late this afternoon and evening does exist. However,
the upper level flow is more easterly instead of northeast which
will make it more difficult for any thunderstorm that develops
over the Chugach Mountains to reach the terminal.