Small Craft Advisory 209, NWS Anchorage, AK

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
444 AM AKST Mon Mar 2 2020

.ANALYSIS AND UPPER LEVELS...

An area of high pressure remains centered over central Russia at
the surface and aloft. Closer to home, a 990 mb low is centered
just east of Anchorage, with a pair of 1006 mb lows centered just
south of Amchitka and south of False Pass respectively.

&&

.MODEL DISCUSSION...

The numerical models remain in good agreement in the synoptic
pattern through the weekend, with just some minor differences in
the details with disturbances passing through the region aloft, as
much colder air invades the region by mid week, as a deep mid-level
system develops just south of Prince William Sound.

&&

.AVIATION...

PANC...Mainly light winds will persist through the TAF period, but
there will be a few gusts near 20 knots through the morning.
Otherwise, look for ceilings in the 1500 to 2500 feet range to
lift into VFR criteria by afternoon, with the light snow also
decreasing in coverage for the afternoon/evening hours.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2)...

The upper level trough will move though the Cook Inlet and Susitna
Valley region this afternoon and that will bring an end of the
snow in these regions. It will linger over the Copper River Basin
keeping some snow there until early Tuesday.

Gusty southwest winds are moving up Cook Inlet this morning. They
have been in Homer much of the night and made it into west
Anchorage early this morning. The recent snowfall may bring some
blowing and drifting snow to roadways this morning. It is not
expected to create widespread low visibilities, but is something
to be aware of if traveling.

Radar imagery overnight indicates that the southwesterly flow has
created a good amount of upsloping snow overnight. This brought in
heavier snowfall amounts along the Hillside and will also allow the
snow to linger a bit longer in the Palmer area today.

The Copper River Basin looks to be in line to 4-8 inches of snow
today through tonight. Therefore a Winter Weather Advisory for
snow was not issued.

&&

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

Snow showers have begun to taper off across the Alaska Peninsula
as a ridge continues to build over the Bering Sea. Northerly flow
will bring cold and dry conditions to most of the southwest through
Wednesday.

&&

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

A weak area of low pressure west of Adak will bring gales over
the southwestern Bering through this morning. Scattered snow
showers are also likely along the western Aleutians. This low will
then weaken and move south of the Chain tonight. Cold and dry
conditions will become the dominant weather type through Wednesday
as northerly flow associated with a ridge over the Bering takes
over. By Wednesday night, another front will approach the western
Aleutians.

&&

.MARINE (Days 3 through 5...Wednesday through Friday)...

A low in the northeastern Gulf gradually weakens and moves
southward. A building ridge of high pressure in place over the
Bering will create a strong pressure gradient, producing gales
over the eastern Bering and Pacific side of the Alaska Peninsula.
Channeled gaps and passes could see storm force winds at times
during the day on Wednesday. These strong northerly winds could
persist through Thursday as the ridge moves eastward. By Wednesday
afternoon a strong area of low pressure approaches the western
Aleutians bringing another round of gale force winds to the
Bering. Though there is still uncertainty, the current track of
the low is to the southeast, centered south of Sand Point by Fri
morning.

&&

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

An upper level low over the western Aleutians moves southeastward
into the western Gulf, giving way to a broad upper level ridge
moving into place over the Bering by Friday morning. Upstream of
this ridge, another deep upper level low moves in, forcing the
ridge eastward toward mainland Alaska. Model solutions are
trending toward strengthening this low as the upper level trough
digs sharply to the south over the weekend. As it does so, model
solutions indicate another strong surface low could impact the
Southwest coast, and eventually the rest of the southern mainland,
Saturday into Sunday.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Winter Weather Advisory 145
MARINE...Gale Warning 119 120 125 130 131 132 138 139 351 352
         Heavy Freezing Spray Warning 121 129 130 138 139 150 165
         179 185 412 414

FIRE WEATHER...NONE.

&&

SYNOPSIS AND MODEL DISCUSSION...PD
SOUTHCENTRAL ALASKA...EZ
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...AK
MARINE/LONG TERM...KO

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ANCHORAGE AK
317 PM AKST MON MAR 2 2020

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

0130 PM     SNOW             GATEWAY                 61.56N 149.32W
03/02/2020  E7.0 INCH        MATANUSKA-SUSITNA  AK   CO-OP OBSERVER

            SPOTTER REPORTED 7 INCHES OF SNOW.

&&

AP

PRELIMINARY LOCAL STORM REPORT...CORRECTED
NATIONAL WEATHER SERVICE ANCHORAGE AK
321 PM AKST MON MAR 2 2020

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

0500 AM     SNOW             BIG LAKE                61.54N 149.83W
03/02/2020  E10.0 INCH       MATANUSKA-SUSITNA  AK   NWS EMPLOYEE

            CORRECTS PREVIOUS SNOW REPORT FROM BIG LAKE.
            SPOTTER REPORTED 10 INCHES. STILL SNOWING AS
            OF 5AM.

&&

AP

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ANCHORAGE AK
330 PM AKST MON MAR 2 2020

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

0200 PM     SNOW             BIG LAKE                61.54N 149.83W
03/02/2020  M12.0 INCH       MATANUSKA-SUSITNA  AK   NWS EMPLOYEE

            SPOTTER MEASURED 12 INCHES OF SNOW.

&&

ED

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ANCHORAGE AK
339 PM AKST MON MAR 2 2020

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

0338 PM     SNOW             TALKEETNA AIRPORT       62.32N 150.10W
03/02/2020  M8.0 INCH        MATANUSKA-SUSITNA  AK   TRAINED SPOTTER

            TALKEETNA FSS REPORTED 8 INCHES OF SNOW AT
            THE AIRPORT.

&&

ED

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ANCHORAGE AK
340 PM AKST MON MAR 2 2020

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

0339 PM     SNOW             PARKS HWY/TALKEETNA SPU 62.13N 150.04W
03/02/2020  E12.0 INCH       MATANUSKA-SUSITNA  AK   TRAINED SPOTTER

            SPOTTER ESTIMATED 12 INCHES OF SNOW AT THE
            JUNCTION OF THE PARKS HIGHWAY WITH TALKEETNA
            SPUR ROAD.

&&

ED

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ANCHORAGE AK
347 PM AKST MON MAR 2 2020

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

0347 PM     SNOW             CHULITNA                62.80N 149.91W
03/02/2020  E4.0 INCH        MATANUSKA-SUSITNA  AK   PUBLIC

            SPOTTER REPORTED 4 INCHES OF SNOW SINCE 10PM
            AKST ON MARCH 1ST.

&&

ED