Three back-to-back snowstorms impacted Southcentral and, to a lesser degree, Southwest Alaska over the course of an 11-day window in early December. These snowfall events resulted in particularly significant impacts to the Matanuska-Susitna Borough and Anchorage Borough areas. These conditions occurred as a highly amplified and transitory pattern affected Southern Alaska, bringing 3 to 5 feet of snow to the Matanuska-Susitna and Anchorage Boroughs within the December 5 to 15, 2022 window.
There were a number of commonalities between the three snow events as follows:
1. All snowstorms occurred as a result of frontogenetically induced lift and associated banded snow.
2. All snowstorms occurred in conjunction with a mature trough, indicating increased instability associated with the pattern.
3. All snowstorms were reinforced by some version of an atmospheric river feeding the system.
4. All snowstorms were associated with a ���weak��� surface low. More frequently during the winter months, strong lows and associated wind fields produce upslope/downslope effects which tend to limit widespread heavy precipitation to the Gulf coast areas. In this case, winds crossing the mountains were generally weak, which allowed for a particularly long period of snow west of the Kenai and Chugach Mountains.
It is uncommon to see three storms in a row with such similar characteristics.
In all cases, these ingredients came together to produce abundant snowfall, with the heaviest snowfall generally falling across the higher elevations. The three events occurred December 6-7, 2022, December 11-12, 2022, and December 14-15, 2022, resulting in 3 to 5 feet of snow total over the course 11-day period. Periods of light snowfall in between these dates were noted, but did not have a meaningful impact on snow totals.
These snowfall events hit a few records. For instance, in the city of Anchorage, they hit the 14th highest snowfall amount for a 2-day period December 11-12, 2022 with 16.2 inches of snow. More notably, the only other 11-day period to see higher amounts on record was in 1996 with 44.6 inches, while this 11-day period measured 41.1 inches of snow. To put this event in perspective, these systems pushed Anchorage to the third snowiest snow-year to date and within six tenths of an inch of the snowiest December on record as of December 16, 2022.

Winter Storm in ANCHORAGE MUNI TO BIRD CREEK, ALASKA
From 13-DEC-22 17:22:00 to 15-DEC-22 06:00:00 (AKST-9)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A third round of heavy snow occurred December 14 through 15 resulting in about a foot of snow across the Anchorage Borough. This snowfall was produced as a tropical moisture plume spread northward and combined with an upper-level disturbance transitioning across the state. The bulk of the snowfall arrived late Wednesday afternoon and continued through Thursday morning. Unlike the last two snow events, snow fell in a more uniform manner. Snowfall reports received ranged from 7.5 inches to 12 inches within a 12 hour period, on top of the snowfall still on the ground from the previous two December snowfall events, leading to increased impacts across the Borough. A member of the public reported 11.7 inches in Eagle River and another reported 12 inches on Northern Lights Blvd within a 12 hour period.

Heavy Snow in MATANUSKA VALLEY, ALASKA
From 13-DEC-22 17:22:00 to 15-DEC-22 06:00:00 (AKST-9)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A third round of heavy snow occurred December 14 through 15 resulting in about a foot of snow across the Matanuska Valley, on top of the snowfall still on the ground from the previous two December snowfall events, leading to increased impacts across the Valley. This snowfall was produced as a tropical moisture plume spread northward and combined with an upper-level disturbance transitioning across the state. The bulk of the snowfall arrived late Wednesday afternoon and continued through Thursday morning. Unlike the last two snow events, snow fell in a more uniform manner. The verifying observation came in from Big Lake where 16 inches of new snow were measured over a 12 hour period.

Heavy Snow in COPPER RIVER BASIN, ALASKA
From 13-DEC-22 17:22:00 to 15-DEC-22 13:30:00 (AKST-9)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A third wave of heavy snow hit southcentral Alaska within an 11-day period in early December. This snowfall was produced as a tropical moisture plume spread northward and combined with an upper-level disturbance transitioning across the state. The bulk of the snowfall arrived late Wednesday afternoon and continued through Thursday morning. Unlike the last two snow events, snow fell in a more uniform manner. A member of the public measured 24 inches of new snow in a 24 hour period in Slana near the Tok Cutoff. Other observations ranged from 6 to 9 inches along the road system.

Heavy Snow in SUSITNA VALLEY, ALASKA
From 13-DEC-22 17:22:00 to 15-DEC-22 06:00:00 (AKST-9)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: County Official

A third round of heavy snow occurred December 14 through 15 resulting in about a foot of snow across the southern portion of the Susitna Valley. This snowfall was produced as a tropical moisture plume spread northward and combined with an upper-level disturbance transitioning across the state. The bulk of the snowfall arrived late Wednesday afternoon and continued through Thursday morning. Unlike the last two snow events, snow fell in a more uniform manner. Taunnie Boothby, the Matanuska-Susitna Borough Floodplain Manager, reported a total of 14 inches of new snow in a 24 hour period, 14 miles up the Willow-Fishhook Road.

Winter Weather in KUSKOKWIM DELTA, ALASKA
From 11-DEC-22 14:49:00 to 13-DEC-22 04:36:00 (AKST-9)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Chefornak and Toksook webcams showed visibilities of about a 1/2 mile; Kipnuk observations showed 1/2 mile or less from 00:32z-0124Z.

Winter Weather in BRISTOL BAY, ALASKA
From 12-DEC-22 04:25:00 to 13-DEC-22 04:36:00 (AKST-9)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

The Cape Newenham observation showed visibilities of 1/2 mile or less from 2336z-0316z; the Platinum observation showed visibilities of 1/2 mile or less several times between 0045z-0242z.

Winter Weather in BRISTOL BAY, ALASKA
From 13-DEC-22 14:30:00 to 15-DEC-22 00:01:00 (AKST-9)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: SNOTEL

Illiamna SNOTEL measured a snow depth difference of about 8 inches.

Heavy Snow in NERN P.W. SND, ALASKA
From 13-DEC-22 17:22:00 to 15-DEC-22 00:15:00 (AKST-9)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

A third wave of heavy snow hit southcentral Alaska within an 11-day period in early December. This snowfall was produced as a tropical moisture plume spread northward and combined with an upper-level disturbance transitioning across the state. The bulk of the snowfall arrived late Wednesday afternoon and continued through Thursday morning. Unlike the last two snow events, snow fell in a more uniform manner. DOT foremen reported 28 inches of new snowfall between December 14th and 15th. The Valdez SNOTEL reported about 18 inches of snow depth difference over the same period.