Gale Warning 280, NWS Anchorage, AK

644 
FZAK61 PAFC 012319
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
319 PM AKDT Sat Apr 1 2023

Offshore waters forecast for the Gulf of Alaska West of 144W

Wind forecasts reflect the predominant speed and direction
expected. Sea forecasts represent an average of the highest
one-third of the combined wind wave and swell height.

PKZ399-021500-
319 PM AKDT Sat Apr 1 2023
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...

A 1000 mb low at 56N 140W moves southeast to the North Pacific Sun 
morning. A 1010 mb low forms 60N 146W Sun morning and moves to 58N 
140W Sun night. A 1005 mb North Pacific low moves to 56N 153W Mon 
afternoon.

$$

PKZ351-021500-
Gulf of Alaska Offshore North of 57N and West of 144W-
319 PM AKDT Sat Apr 1 2023

.TONIGHT...NW wind 15 to 30 kt. Seas 6 to 11 ft.
.SUN...W wind 20 to 30 kt. Seas 7 to 12 ft.
.SUN NIGHT...W wind 15 to 25 kt diminishing to up to 20 kt after
midnight. Seas 6 to 11 ft.
.MON...S wind up to 20 kt. Seas 3 to 6 ft.
.MON NIGHT...SE wind 15 to 30 kt. Seas 3 to 8 ft.
.TUE THROUGH THU...NW wind 15 to 30 kt. Seas 5 to 10 ft.

$$

PKZ352-021500-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
319 PM AKDT Sat Apr 1 2023

.TONIGHT...NW wind 30 kt. Seas 9 to 14 ft.
.SUN...W wind 25 kt. Seas 8 ft.
.SUN NIGHT...W wind 10 to 25 kt. Seas 5 to 9 ft. Rain.
.MON...S wind 10 to 20 kt. Seas 3 to 7 ft.
.MON NIGHT...S wind 10 to 25 kt. Seas 4 to 8 ft.
.TUE THROUGH THU...W wind up to 20 kt. Seas 5 to 8 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
413 PM AKDT Fri Mar 31 2023

.ANALYSIS AND UPPER LEVELS...

In the mid and upper levels, a broad area of low pressure
stretches across much of the mainland, with shortwaves moving
through the northwest flow over far southwest Alaska and the
southern Bering. A ridge of high pressure is building over the
western and northern Bering sea. At the surface, a low pressure
center is located over the Gulf.

Scattered light snow showers were occurring across mainly coastal
areas of Southcentral and points from Gulkana eastward in
association with the low in the Gulf. Areas of light snow were
also occurring over Southwest AK, the AKPen, and eastern/central
Aleutians associated with the shortwaves moving through the
northwest flow.

&&

.MODEL DISCUSSION...

While model solutions through the weekend are generally
consistent, there are still differences in regard to the speed of
the system and its associated front coming out of Siberia,
although those differences are lessening. Models show the center
of that low moving onshore close to the Seward Peninsula, with its
front swinging into SW AK tomorrow. However the front will
struggle to make it very far east with a high pressure ridge
building between that low and the Gulf low.

Meanwhile, a low pressure system sitting in the northern Gulf
will spin roughly in place until early tomorrow morning before
moving off to the southeast. The large low pressure system south
of the western Aleutians is expected to gradually move northeast
into the southern Bering behind the Siberian low.

&&

.AVIATION...

PANC...VFR conditions are expected through Saturday. Winds will
switch to the north this evening and there may be a periods of
stronger winds to 15 kt through the overnight hours.

&&.

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

Lingering light snowfall in the Chugach mountains along with the
possible flurry at lower elevations will diminish overnight
tonight for Southcentral. Offshore flow will continue, with some
gusts possible near Kodiak City, Valdez/Thompson Pass, Seward, and
Whittier. As a shortwave ridge builds in, a clearing trend will
be observable for much of Southcentral beginning Saturday, as well
as diminishing those gusty conditions by Saturday night. This
weekend will be clear and dry across Southcentral. The next system
to approach Southcentral, namely Kodiak Island, will be the
leading edge of a front expected to move in beginning Monday
morning. Precipitation associated with this system is currently
expected to be snowfall, with some wintry mix along the coastline.
Stay tuned as we investigate the propagation of this system and
how it may impact mainland Southcentral.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 through 3: Today
through Monday)...

A weak shortwave is moving across Bristol Bay and the Kuskokwim
Valley and will produce a few snow showers through this evening. A
transitory ridge will move across the area tonight and tomorrow
morning with clouds clearing tonight across most of the area.
Winds will be elevated enough that fog should not be an issue
tonight and tomorrow morning. An upper level low will move out
Siberia pushing a cold front towards the Kuskokwim Delta by
tomorrow evening this will bring a band of light snow with less
than an inch expected. This cold front will move east Sunday
morning with some areas of light snow from Aniak to Sleetmute and
south to near Iliamna. Another ridge of high pressure will move
across Southwest Alaska Sunday afternoon through Sunday night with
a brief period of clearing skies. However, by Monday morning an
occluded front moving across the Bering will bring light snow
across the area on Monday with 1 to 3 inches of snowfall expected.
Most areas should remain snow as temperatures stay in the low to
mid 30s.

Across the AKPen northwest flow with gusty northwest winds will
continue through tomorrow morning with a few snow showers
possible. The winds will relax by Saturday afternoon and into
Sunday with nice weather expected. The occluded front mentioned
above will move across the AKPen Sunday and Monday with a period
of snow changing to rain on Sunday and a mix of rain and snow on
Monday. Up to an inch of snowfall is possible.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 through 3)...

Mostly quiet weather through tonight as a ridge dominates most of
the Bering and Aleutians with mostly cloudy conditions. A low
pressure system will bring an end to the quiet weather as it
approaches the western Aleutians tonight producing gales with
snow changing to rain. This low will push an occluded front across
the Bering and Aleutians Saturday and Sunday with pockets of
gales and widespread rain. This front will also bring a period of
snow across the Pribilof Islands with 1 to 3 inches of snow
possible on Sunday before changing to rain. This low will track
across the Bering on Monday with rain and snow showers expected
from the Pribilof Islands to the western Aleutians.

&&

.LONG TERM FORECAST (Days 4 through 7: Tuesday through Friday)...

The long term features several shortwave troughs and low pressure
systems moving across the region as the jet stream remains near
the Aleutians extending towards the Gulf. This will drive the
first in a series of low pressure systems into the Gulf on Tuesday
which may bring some Gales across parts of the Gulf with coastal
rain and inland snow. A second and potentially stronger complex low
pressure system moves across the Bering on Tuesday moving into the
Gulf on Wednesday. All of the models show deepening of this system
as it moves towards the Gulf with several shortwaves combining
energy into one system across the Gulf. However, there are
differences on how strong this low will be with the GFS the
strongest and the EC and GEM showing a weaker low. But given the
fact that all the models including the ensembles are showing a
deepening low we are leaning towards the stronger GFS solution. As
we head into Thursday the models depict another low pressure
system moving from Kamchatka towards the Bering and Aleutians.
Once again the GFS is stronger and also slower as this system
deepens, with a more progressive and weaker solution for the EC
and GEM. The ensembles seem to favor the stronger solution on
Thursday, however the surface lows are scattered over a broad
area leading to low confidence on the track and timing. Across
the Gulf a brief break on Thursday before the next low mentioned
across the Bering moves into the Gulf by Friday.

&&

SYNOPSIS AND MODEL DISCUSSION...NR
SOUTHCENTRAL ALASKA...CL
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...RC
LONG TERM...RC