Small Craft Advisory 985, NWS Anchorage, AK

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
543 AM AKST Thu Nov 9 2023

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

The strong low causing the snow, rain, and wind across
Southcentral is about to make landfall in Western Prince William
Sound early this morning. It will then move over the Anchorage
area and into the Susitna Valley this afternoon. This low track is
bringing Anchorage northward in the warm sector of the low and
therefore mixing rain and snow in Anchorage. The Matanuska Valley
has had some rain overnight (over quarter inch at the Palmer
airport) with the warmest air moving over it. Areas south of
Anchorage on the Kenai Peninsula remaining mostly snow due to
being in the cold sector of the storm.
This low is tracking a little farther north than was expected a
day ago which kept Anchorage and areas farther south in the cold
sector of the system and kept Anchorage in the snow with rain just
mixing in for the Anchorage area after about 4 AM. A few miles in
the low track can make a world of difference in precipitation
type. As this low moves to the north, the Cook Inlet region
including Anchorage will get gusty southerly winds that jump
temperatures into the mid to upper 30s with over 40 degrees in
some areas. Precipitation should have mostly ended by the time
this happens. Strong southerly winds are also expected today in
the Copper River Basin as the low and associated front track
northward. Expect temperatures to rise into the upper 30s to lower
40s at lower elevations of the Copper Basin today with these
winds.

&&

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

An occluded low is stretched across the Central Aleutians this
morning with the triple point situated south of the islands.
Scatterometer observations confirm gale force winds for the back
side of the low, though storm force winds will remain possible
through this morning from Amchitka to Adak. Northwesterly flow
across the Bering will become more widespread this afternoon and
will even spread into Southwest Alaska. There is a high likelihood
for bands of convective showers developing across the Bering and
the Aleutians. For the Kuskokwim Delta, fog will be possible this
morning once the flow switches to onshore. Snow is also moderately
possible (40 to 60 percent) with upslope flow onto the Kuskokwim
mountains. Chances start to gradually taper off Friday morning
from the Western Bering, then the Pribilofs by Friday night, and
the Eastern Bering by about Saturday morning. Snow in Bethel and
the Kuskokwim Delta become more confined to the mountains by late
Friday morning. There will be a warm front that will be following
the back edge of those showers and a large ridge of high pressure
will dominate the Bering Sea on Saturday. The parent low from the
aforementioned warm front will move across Kamchatka Saturday and
its associated cold front will reach the Western Aleutians by
Saturday afternoon. Plenty of moisture and warm air will be
available with this system and much of the precipitation type will
be rain. The front will reach the Pribilofs on Sunday and
continue onto the entire western Alaska coast Sunday afternoon and
night. Convective bands of precipitation will trail behind the
front and flow will become more zonal before the next low quickly
moves into the Bering Sea next week. Gales will be common with the
frontal passages.

&&

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

More active weather is on the menu through Wednesday, and
forecast models slip into a better consensus through the period.
The low center in the Gulf slides to the Southeast, and the
shortwave ridge moves across the Southern half of the Mainland by
midweek. Gale force winds are expected along the Alaska Peninsula,
around Kodiak Island and the Southern Kenai Peninsula for Sunday.
The first well developed low center tracks across the Northern
Bering into Northwest Alaska for Monday. This brings locally heavy
precipitation, gale force winds with storm force gusts and the
potential for coastal flooding to Western Alaska through Monday.
On its heels, a second strong low enters the Western Bering from
the North Pacific, spreading locally heavy rainfall, widespread
gale force winds and large areas of storm force gusts across the
Bering and Aleutians through Wednesday. These winds spread across
the Southern Bering into Western Alaska, increasing the chances
for coastal flooding through Wednesday. The leading edges of this
low also spread locally heavy precipitation along the Western
Alaska Range, and from the Eastern Kenai Peninsula to the Canadian
Border through Wednesday.

KZ

&&

.AVIATION...

PANC...

Snow intensities are expected to be lighter throughout today, with
some breaks between snow bands. Warmer air aloft may allow for
periods of a rain/snow mix this morning as well. Visibilities
will increase to MVFR this morning and improve again to VFR by
late afternoon/early evening. Snow is expected to taper off by
this evening.

KM

&&

Preliminary Local Storm Report
National Weather Service Anchorage AK
251 PM AKST Thu Nov 9 2023

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

0249 PM     Snow             9 SE Anchorage          61.10N 149.72W
11/09/2023  M27.0 inch       Anchorage          AK   Trained Spotter

            Located on the Upper Hillside. 27 inches of
            snowfall accumulation with the Winter Storm.
            34 inches of accumulation since Sunday.

&&

CL

Preliminary Local Storm Report
National Weather Service Anchorage AK
259 PM AKST Thu Nov 9 2023

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

1256 PM     Snow             Anchorage Hillside      61.10N 149.75W
11/09/2023  M22.0 inch       Anchorage          AK   Public

            Storm total. Snowing heavily at time of
            report.

0146 PM     Snow             Eagle River             61.32N 149.54W
11/09/2023  M4.0 inch        Anchorage          AK   Trained Spotter

            A trained spotter measured 4.0 inches of
            snow since 7 am. Snowing at time of report.

&&

Preliminary Local Storm Report
National Weather Service Anchorage AK
314 PM AKST Thu Nov 9 2023

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

0250 PM     Snow             Southeast Anchorage     61.10N 149.82W
11/09/2023  M23.5 inch       Anchorage          AK   NWS Employee

            An NWS employee measured 23.5 inches of snow
            (storm total). Snow depth of 29 inches. Snow
            has ended.

&&

Preliminary Local Storm Report
National Weather Service Anchorage AK
326 PM AKST Thu Nov 9 2023

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

0200 PM     Snow             Girdwood                60.95N 149.12W
11/09/2023  M36.5 inch       Anchorage          AK   Trained Spotter

            A trained spotter reported 36.5 inches of
            snow since 3 pm yesterday (Nov 8). Snow
            switched briefly to rain from 2:30 to 3:00
            am. Light drizzle as of report at 2 pm.

&&

Preliminary Local Storm Report
National Weather Service Anchorage AK
341 PM AKST Thu Nov 9 2023

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

0315 PM     Snow             West Anchorage          61.15N 149.93W
11/09/2023  M16.6 inch       Anchorage          AK   NWS Employee

            An NWS employee measured 16.6 inches of snow
            (storm total). Liquid equivalent 1.48
            inches.

&&

Preliminary Local Storm Report
National Weather Service Anchorage AK
343 PM AKST Thu Nov 9 2023

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

0249 PM     Snow             Anchorage Hillside      61.11N 149.73W
11/09/2023  M22.0 inch       Anchorage          AK   Trained Spotter

            A trained spotter measured 22.0 inches of
            snow. Storm total.

&&