National Weather Service Raw Text Product

499 
FXAK68 PAFC 191302
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
502 AM AKDT Sun May 19 2024

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

A strong and unseasonably cool upper level trough extending south
and east from the the Gulf of Anadyr to the Central Gulf of 
Alaska will weaken and lift north and east today as a strong 
shortwave rotating around the trough moves east through the 
Central Gulf of Alaska today and over the Panhandle on Monday. 
Weak ridging builds into the Western Gulf of Alaska on MOnday.

On the surface a 1001 mb low currently located approximately 50 
nm east of Kodiak City will continue to weaken this morning as it 
pushes to the east into the Central Gulf today and into the 
Eastern Gulf tonight. A front wrapping around the low continues 
to push slowly north and is near Homer at this time. Strong 
southeasterly winds ahead of the front will diminish later this 
morning especially through Turnagain and Knik Arms where 
southeast wind gust in the 25 to 35 mph range continue early this 
morning. Rain has diminished over Kodiak Island as the front 
passed to the north. Expect unsettled conditions over Southcentral
today with the rain over the Eastern Kenai and Prince William 
Sound slowly diminishing from south to north today as the front 
continues to weaken push north and east. Copper River Basin will 
remain unsettled with clouds and showers expected through the day.
Winds, clouds and precipitation will decrease late Monday and 
into Tuesday as a weak ridge builds into the northern Gulf of 
Alaska.

A low over the Bering pushes another front into Southcentral
Tuesday morning, with rain likely overspreading much of
Southcentral by late Tuesday afternoon. A more southerly/southwesterly
flow aloft as compared to an easterly/southeasterly flow aloft with
this next low will bring a better chance of rain to the the 
western Kenai, Anchorage Bowl, and MatSu areas. 

-CC 

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA, THE BERING SEA AND THE 
ALEUTIANS (Days 1 through 3: Today through Tuesday night)...

Due to good model consensus and run-to-run consistency, few 
changes have been made to the forecast through Monday. By Tuesday,
however, forecast confidence diminishes as models differ on the 
evolution and timing of an occluding Bering Sea low. As such, there
may be shifts in wind speed as well as precipitation timing and 
amounts in subsequent forecast updates.

The negatively tilted trough and upper-level low that brought 
much of yesterday's weather will continue to move eastward into 
the Gulf of Alaska through today. Shower activity over Southwest 
Alaska should largely taper off through today, though the 
combination of daytime heating and weak shortwaves wrapping around
the low could lead to isolated to widely scattered afternoon 
showers.

Out west, a series of Kamchatka lows and fronts will begin to
impact the Bering Sea and Aleutian Chain. The first frontal system
is currently over the Western and Central Bering/Aleutians 
spreading rain and winds up to 25 kt as it moves to the east. 
The second system, a Kamchatka low, moves across the Western 
Bering through today, merging with the first system as it
reaches the Pribilof Islands. This now energized front will bring
light to moderate rain and small craft winds as it sweeps east
across the Bering Sea, reaching the coast of Southwest Alaska
around midday Monday.

As the front moves into Southwest Alaska for the second half of 
Monday, coastal Southwest Alaska will initially see the brunt of
precipitation. However, by late Monday night into early Tuesday
morning, an incoming stout shortwave will intensify rainfall and
progress the front eastward across Southern Alaska. Cold air aloft
moves in behind the front, keeping showers over parts of the
Bering/Aleutians and over much of Southwest Alaska through Tuesday.

-DAN/KC

&&

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

A persistent northwest to southeast oriented longwave trough will
remain over the Bering with a shortwave on the southern terminus bending
into the northern Gulf through Sunday. A second upper level low
will move from Kamchatka into the central Bering on Tuesday
followed by a third on Thursday. This series of low pressure 
systems will bring gusty wind, coastal rain showers and interior 
cloudy and isolated rain showers. Toward the end of next week, an 
area of high pressure will push from the North Pacific into the 
Bering Sea and nudge the longstanding trough eastward.


&&

.AVIATION...

PANC...VFR conditions will persist. Strong southeasterly winds 
out of Turnagain are expected to persist past midnight tonight. It
does look like the Turnagain Arm winds will then turn down the
Inlet as a low moves along the southern Kenai Peninsula overnight
and turns the pressure gradient down-Inlet. There is the potential
for some wind shear when this happens, but it will likely be above
2000 ft.

&&


$$

961 
FXAK68 PAFC 191331
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion National 
Weather Service Anchorage AK 502 AM AKDT Sun May 19 2024

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

A strong and unseasonably cool upper level trough extending south 
and east from the the Gulf of Anadyr to the Central Gulf of Alaska 
will weaken and lift north and east today as a strong shortwave 
rotating around the trough moves east through the Central Gulf of 
Alaska today and over the Panhandle on Monday. Weak ridging builds 
into the Western Gulf of Alaska on MOnday.

On the surface a 1001 mb low currently located approximately 50 nm 
east of Kodiak City will continue to weaken this morning as it 
pushes to the east into the Central Gulf today and into the Eastern 
Gulf tonight. A front wrapping around the low continues to push 
slowly north and is near Homer at this time. Strong southeasterly 
winds ahead of the front will diminish later this morning especially 
through Turnagain and Knik Arms where southeast wind gust in the 25 
to 35 mph range continue early this morning. Rain has diminished 
over Kodiak Island as the front passed to the north. Expect 
unsettled conditions over Southcentral today with the rain over the 
Eastern Kenai and Prince William Sound slowly diminishing from south 
to north today as the front continues to weaken push north and east. 
Copper River Basin will remain unsettled with clouds and showers 
expected through the day.
Winds, clouds and precipitation will decrease late Monday and into 
Tuesday as a weak ridge builds into the northern Gulf of Alaska.

A low over the Bering pushes another front into Southcentral Tuesday 
morning, with rain likely overspreading much of Southcentral by late 
Tuesday afternoon. A more southerly/southwesterly flow aloft as 
compared to an easterly/southeasterly flow aloft with this next low 
will bring a better chance of rain to the the western Kenai, 
Anchorage Bowl, and MatSu areas. 

-CC 

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA, THE BERING SEA AND THE 
ALEUTIANS (Days 1 through 3: Today through Tuesday night)...

Due to good model consensus and run-to-run consistency, few changes 
have been made to the forecast through Monday. By Tuesday, however, 
forecast confidence diminishes as models differ on the evolution and 
timing of an occluding Bering Sea low. As such, there may be shifts 
in wind speed as well as precipitation timing and amounts in 
subsequent forecast updates.

The negatively tilted trough and upper-level low that brought much 
of yesterday's weather will continue to move eastward into the Gulf 
of Alaska through today. Shower activity over Southwest Alaska 
should largely taper off through today, though the combination of 
daytime heating and weak shortwaves wrapping around the low could 
lead to isolated to widely scattered afternoon showers.

Out west, a series of Kamchatka lows and fronts will begin to impact 
the Bering Sea and Aleutian Chain. The first frontal system is 
currently over the Western and Central Bering/Aleutians spreading 
rain and winds up to 25 kt as it moves to the east. The second 
system, a Kamchatka low, moves across the Western Bering through 
today, merging with the first system as it reaches the Pribilof 
Islands. This now energized front will bring light to moderate rain 
and small craft winds as it sweeps east across the Bering Sea, 
reaching the coast of Southwest Alaska around midday Monday.

As the front moves into Southwest Alaska for the second half of 
Monday, coastal Southwest Alaska will initially see the brunt of 
precipitation. However, by late Monday night into early Tuesday 
morning, an incoming stout shortwave will intensify rainfall and 
progress the front eastward across Southern Alaska. Cold air aloft 
moves in behind the front, keeping showers over parts of the 
Bering/Aleutians and over much of Southwest Alaska through Tuesday.

-DAN/KC

&&

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

A persistent northwest to southeast oriented longwave trough will 
remain over the Bering with a shortwave on the southern terminus 
bending into the northern Gulf through Sunday. A second upper level 
low will move from Kamchatka into the central Bering on Tuesday 
followed by a third on Thursday. This series of low pressure systems 
will bring gusty wind, coastal rain showers and interior cloudy and 
isolated rain showers. Toward the end of next week, an area of high 
pressure will push from the North Pacific into the Bering Sea and 
nudge the longstanding trough eastward.


&&

.AVIATION...

PANC...VFR conditions will persist. Light northerly winds shift to 
the southeast for the afternoon/evening as a weak Turnagain Arm wind 
develops. There is potential for light rain showers this afternoon 
as well, which could drop ceilings below 5000 ft. Southeasterly 
winds will diminish through the evening hours, with ceilings rising 
back above 5000 ft as any potential showers clear out.

CQ

&&


$$