Gale Warning 347, NWS Anchorage, AK

977 
FZAK61 PAFC 031141
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
341 AM AKDT Thu May 3 2018

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.

PKZ399-040215-
341 AM AKDT Thu May 3 2018
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...

A front in the western Gulf moves to the northeastern Gulf
tonight. A 986 mb low at 52N 163W this afternoon moves to 56N 158W
at 973 mb tonight. The low then moves north over Bristol Bay and 
continues inland Fri night.

$$

PKZ351-040215-
Gulf of Alaska Offshore North of 57N and West of 144W-
341 AM AKDT Thu May 3 2018

...GALE WARNING FRIDAY...

.TODAY...SE wind 20 to 30 kt becoming SW 20 kt in the afternoon. 
Seas 7 ft. Rain.
.TONIGHT...SW wind 20 kt becoming SE 20 to 30 kt after midnight. 
Seas 8 ft. Rain.
.FRI...S wind 20 to 35 kt. Seas 9 to 14 ft. Rain.
.FRI NIGHT...S wind 10 to 25 kt. Seas 13 ft.
.SAT THROUGH SUN...S wind 10 to 25 kt. Seas 9 to 13 ft.
.MON...SE wind 10 to 20 kt. Seas 5 ft.

$$

PKZ352-040215-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
341 AM AKDT Thu May 3 2018

...GALE WARNING TONIGHT AND FRIDAY...

.TODAY...SW wind 15 to 25 kt. Seas 5 to 9 ft.
.TONIGHT...S wind 15 to 25 kt increasing to 20 to 35 kt after
midnight. Seas 8 to 12 ft. Rain.
.FRI...S wind 20 to 35 kt. Seas 9 to 16 ft. Rain.
.FRI NIGHT...S wind 15 to 30 kt. Seas 11 to 16 ft.
.SAT THROUGH SUN...SW wind 10 to 25 kt. Seas 9 to 14 ft.
.MON...SE wind 10 to 25 kt. Seas 6 ft.

$$

546 
FZAK61 PAFC 032323
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
323 PM AKDT Thu May 3 2018

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.

PKZ399-041330-
323 PM AKDT Thu May 3 2018
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...
A front in the western Gulf reaches the northeastern Gulf Fri 
afternoon. A complex 988 mb low at 52N 163W moves to 56N 158W at 
974 mb tonight then it will move inland Fri afternoon at 973 mb. 
The associated front remains nearly stationary across the central 
Gulf through Sat afternoon.

$$

PKZ351-041330-
Gulf of Alaska Offshore North of 57N and West of 144W-
323 PM AKDT Thu May 3 2018

.TONIGHT...S wind 20 to 30 kt. Seas 8 ft. Rain.
.FRI...S wind 30 kt. Seas 9 to 14 ft. Rain.
.FRI NIGHT...S wind 15 to 25 kt. Seas 13 ft.
.SAT...S wind 15 to 25 kt. Seas 11 ft.
.SAT NIGHT...SW wind 10 to 20 kt. Seas 8 to 11 ft.
.SUN THROUGH MON...SE wind up to 20 kt. Seas 5 to 9 ft.
.TUE...SE wind 25 kt. Seas 8 to 13 ft.

$$

PKZ352-041330-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
323 PM AKDT Thu May 3 2018

...GALE WARNING THROUGH FRIDAY...

.TONIGHT...S wind 20 to 35 kt. Seas 8 to 13 ft. Rain.
.FRI...S wind 20 to 35 kt. Seas 9 to 16 ft. Rain.
.FRI NIGHT...S wind 15 to 30 kt. Seas 11 to 14 ft.
.SAT...SW wind 10 to 25 kt. Seas 11 ft.
.SAT NIGHT...SW wind up to 20 kt. Seas 7 to 11 ft.
.SUN THROUGH MON...SE wind 10 to 25 kt. Seas 4 to 8 ft.
.TUE...SE wind 15 to 25 kt. Seas 9 to 14 ft.

$$

835 
FZAK61 PAFC 041137
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
337 AM AKDT Fri May 4 2018

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.

PKZ399-050245-
337 AM AKDT Fri May 4 2018
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...

A 973 mb low at 56N 159W will move inland near 59N 160W at 972 mb
by Sat morning. The associated front will move across the western
Gulf and reach the northeastern Gulf this morning.

$$

PKZ351-050245-
Gulf of Alaska Offshore North of 57N and West of 144W-
337 AM AKDT Fri May 4 2018

.TODAY...S wind 30 kt. Seas 9 to 14 ft. Rain.
.TONIGHT...S wind 15 to 25 kt. Seas 12 ft. Rain.
.SAT...S wind 15 to 25 kt. Seas 11 ft.
.SAT NIGHT...SW wind 10 to 20 kt. Seas 9 ft.
.SUN...E wind up to 10 kt. Seas 4 to 8 ft.
.MON THROUGH TUE...SE wind 15 to 30 kt. Seas 5 to 10 ft.

$$

PKZ352-050245-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
337 AM AKDT Fri May 4 2018

...GALE WARNING TODAY...

.TODAY...S wind 20 to 35 kt. Seas 9 to 16 ft. Rain.
.TONIGHT...S wind 15 to 30 kt. Seas 10 to 14 ft. Rain.
.SAT...SW wind 10 to 25 kt. Seas 11 ft.
.SAT NIGHT...SW wind up to 20 kt. Seas 9 ft.
.SUN...NE wind up to 10 kt. Seas 3 to 8 ft.
.MON...E wind up to 20 kt. Seas 3 to 6 ft.
.TUE...SE wind 10 to 25 kt. Seas 6 to 11 ft.

$$

243 
FZAK61 PAFC 042354
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
354 PM AKDT Fri May 4 2018

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.

PKZ399-051415-
354 PM AKDT Fri May 4 2018
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...
A front begins to track inland along the northern Gulf Coast and 
into the Eastern Gulf for Sat afternoon. Weak ridging edges into the 
Western Gulf by Sun afternoon.

$$

PKZ351-051415-
Gulf of Alaska Offshore North of 57N and West of 144W-
354 PM AKDT Fri May 4 2018

.TONIGHT...S wind 15 to 25 kt. Seas 13 ft. Rain.
.SAT...SW wind 10 to 25 kt. Seas 10 ft.
.SAT NIGHT...SW wind 10 to 20 kt. Seas 10 ft.
.SUN...SE wind 10 kt. Seas 7 ft.
.SUN NIGHT...NE wind up to 10 kt. Seas 3 to 6 ft.
.MON THROUGH WED...SE wind 15 to 30 kt. Seas 5 to 10 ft.

$$

PKZ352-051415-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
354 PM AKDT Fri May 4 2018

.TONIGHT...S wind 15 to 25 kt. Seas 11 to 14 ft. Rain.
.SAT...SW wind 10 to 25 kt. Seas 11 ft.
.SAT NIGHT...SW wind 10 to 15 kt. Seas 9 ft.
.SUN...SE wind up to 10 kt. Seas 5 to 8 ft.
.SUN NIGHT...N wind up to 10 kt. Seas 5 ft.
.MON THROUGH WED...SE wind 10 to 25 kt. Seas 6 to 11 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
522 AM AKDT Wed May 2 2018

.ANALYSIS AND UPPER LEVELS...
A shift in the pattern is underway across the state this morning
as a departing trough continues eastward into the Yukon Territory.
A low in the central Bering is rapidly moving eastward toward
Bristol Bay and deepening as it approaches the Alaska Peninsula.
Primarily upper level zonal flow today will eventually break down
and transition to southerly flow as the leading front moves over
Southcentral. Light areas of rain showers are seen on radar this
morning in Southwestern Alaska and across the Susitna Valley. Most
of Southcentral is fairly clear this morning except for
considerable cloudiness across the Susitna Valley and Copper
River Basin.

&&

.MODEL DISCUSSION...
The numerical models are doing well with the large scale synoptic
pattern through the weekend, but they are still struggling and
differing with regard to key (and important) details as the flow
pattern dramatically amplifies the next three days.

The details are rather complex, but a leading shortwave currently
moving east through the central Bering Sea will strengthen and
stall with the associated front continuing east toward the North
Gulf Coast Thursday. Here, the NAM is the most significant outlier
with both features and was ignored. The ECMWF and GFS were
suitable for this forecast and were favored for the first two
days.

The next low, which will be a diabatic low level warm anomaly
phasing with the Bering parent upper trough, is expected to move
north toward the Alaska Peninsula Thursday night and Friday then
rapidly strengthen as it moves into SW Alaska. Here the models are
still flip-flopping back and forth among runs, but the overall
trend has been for the low to shift farther and farther west, with
the once outlier ECMWF solution now also shifting west. This will
have impacts to the forecast, but it does seem this storm will be
rather intense, quite intense actually, for May. A blend of the
GFS and ECMWF was also favored for this storm which will bring a
laundry list of impacts to Southern Alaska (winds to SW AK,
blustery conditions to most of Southcentral, heavy coastal rain,
etc.). Stay tuned...

&&

.AVIATION...
PANC...VFR conditions will persist. Continued breezy W-SW winds at
the terminal will end this morning. The next burst of more normal
(for this time of year) SE winds will develop off Turnagain Arm
this evening and continue through the overnight before diminishing
late Thursday morning as the down Cook Inlet gradient
strengthens.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2)...
Conditions will be fairly dry across Southcentral today as weak
high pressure builds in. The next system will approach from the
southwest tonight. The front is expected to push into Kodiak
this evening. This front quickly spreads to the northern Gulf
overnight. Gusty east to southeast flow increases along the front
with rain across the Gulf spreading inland. Most of the
precipitation will fall along the coast and coastal mountains, but
some could sneak inland with the flow aloft initially from the
southwest. The next system will rapidly move in from the southwest
Thursday night. This is rather strong system for this time of
year, with Gale force winds over the Gulf and considerable
precipitation moving into the coast by late Thursday night.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 and 2)...
A frontal system in the Bering will begin spreading precipitation
across the Alaska Peninsula today and then to the Southwest
Alaska coast this afternoon and evening. The front will then lift
north and inland over Southwest Alaska tonight through Thursday
before a significantly strong low pressure system tracks in from
the south Thursday night and Friday. Breezy easterly gap winds are
expected to develop out of passes in the Aleutian Range and the
Alaska Range tonight with substantially stronger offshore northeasterly
winds building Thursday night through Friday morning in advance of
the second system.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2)...
North to northwesterly flow will increase through the cold
advection in the western and central Bering over the next several
days. Initially the strongest winds will be associated with the
wrap around frontal band to the west of the surface low near the
Pribilofs. As a rapidly deepening North Pacific surface low
tracks up towards the Alaska Peninsula, the low in the Bering will
be pulled south as the new and rather strong low slingshots north
up towards Bristol Bay Thursday night. As the new low becomes the
dominant feature and tracks north, northwesterly Gales will shift
east from the central Bering into the eastern Bering.

&&

.LONG TERM FORECAST (Days 3 through 7: Friday through Tuesday)...
The very wet weather pattern ongoing at the start of the long-term
forecast will continue through Friday as a strong low, located
either in Bristol Bay or between Kodiak Island and the Alaska
Peninsula, brings a renewed surge of heavy rain to the north Gulf
Coast and snow at the higher elevations of the coastal mountains.
The associated front will also restart the barrier jet along the
Gulf Coast, along with the Turnagain Arm and Knik River Valley
winds. In a change from the past few days, the latest trend in the
models is to keep the surface low further south near Bristol Bay
until Friday night, which in turn will allow it to weaken further
before tracking north into the state. This will prevent winds
through the gaps from getting near warning levels. The winds will
continue into Saturday as the low lifts to near Norton Sound.
However, since by that point the low will be in a much weakened
state, the winds should not increase appreciably. The
precipitation behind the low over southern Alaska should become
more scattered, showery, and favoring the mountains.

The showery weather pattern continues into Sunday with the
potential for an upper level disturbance moving through. Generally
Sunday looks to be the dry day of the group for Southwest Alaska
as it gets in between weather systems. By this point the
disagreements in the models are great enough that the timing can
drastically change. Where the models all agree is that the
weather will be unsettled for most of Southcentral for both
weekend days. The disagreements become even greater moving into
early next week, but for now it appears Monday will be the dry
day in Southcentral. A front and a new low moving into the eastern
Bering looks to return at least some of the area to unsettled
conditions on Tuesday, especially Southwest Alaska.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Ice Jam Flood Advisory for 152 for Kuskokwim River near Aniak.
MARINE...None.

&&

SYNOPSIS AND MODEL DISCUSSION...JA/KO
SOUTHCENTRAL ALASKA...BL
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...JER
LONG TERM...JW

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ANCHORAGE AK
1108 AM AKDT WED MAY 02 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0815 AM     SNOW             19 ESE BUTTE            61.42N 148.52W
05/02/2018  M1.0 INCH                           AK   TRAINED SPOTTER

1000 AM     SNOW             25 SSW MATANUSKA GLACIE 61.47N 148.12W
05/02/2018  M3.0 INCH                           AK   TRAINED SPOTTER

            SNOW STILL FALLING

&&

KUTZ