Accompanying an atmospheric river, a strong winter storm system brought periods of moderate to heavy snow on January 11th and 12th. The northern Cascades, eastern Cascade valleys, and Okanogan Highlands received the greatest snow totals, with a two day snow accumulation of 17.5 at Stevens Pass. Four to eight inches new snow accumulations were common throughout the remainder of the impacted areas. With saturated soils and snow covered branches, these conditions added to the strong frontal winds arriving January 13th causing isolated power outages and fallen trees.

Heavy Snow in WENATCHEE AREA, WASHINGTON
From 11-JAN-21 07:00:00 to 12-JAN-21 07:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

A CoCoRaHS observer, 12 miles northwest of Entiat, recorded 7.0 inches of new snow accumulation.

Heavy Snow in OKANOGAN HIGHLANDS, WASHINGTON
From 11-JAN-21 07:00:00 to 12-JAN-21 07:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

A CoCoRaHS observer, 7.6 miles north of Republic, recorded 4.5 inches of new snow accumulation.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 11-JAN-21 09:00:00 to 12-JAN-21 09:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A member of the public near Mazama reported 12 inches of new snow accumulation.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 11-JAN-21 08:00:00 to 12-JAN-21 08:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A member of the public in Winthrop reported 8.0 inches of new snow accumulation.

Heavy Snow in OKANOGAN HIGHLANDS, WASHINGTON
From 11-JAN-21 08:00:00 to 12-JAN-21 08:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A member of the public, 7 miles north of Molson, reported 5.0 inches of new snow accumulation.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 11-JAN-21 08:00:00 to 12-JAN-21 08:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Park/Forest Service

The Berne WSDOT Camp recorded 15.8 inches of new snow accumulation.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 11-JAN-21 08:00:00 to 12-JAN-21 08:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

A CO-OP observer, 8.6 miles west of Lucerne, recorded 13.9 inches of new snow accumulation.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 11-JAN-21 07:00:00 to 12-JAN-21 07:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

A CoCoRaHS observer, 12 miles north of Leavenworth, recorded 7.5 inches of new snow accumulation.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 11-JAN-21 06:30:00 to 13-JAN-21 06:30:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

The Washington Department of Transportation site at Stevens Pass recorded 17.5 inches of new snow accumulation.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 12-JAN-21 01:00:00 to 12-JAN-21 12:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

The heaviest snow fell in the northern Cascades and eastern Cascade valleys overnight Monday, January 11th, into early Tuesday afternoon. The Cascade valleys received 6 to 10 inches of new snow accumulation. The mountains and passes received 12 to 15 inches. With saturated soils and snow covered branches, the heavy snow caused isolated power outages and fallen trees. The Chelan County Public Utility District reported widespread outages in the county with most restored by the afternoon of January 12th.

Heavy Snow in OKANOGAN HIGHLANDS, WASHINGTON
From 12-JAN-21 01:00:00 to 12-JAN-21 12:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A heavy snow fell overnight into the early morning hours of January 12th. Numerous locations across the Okanogan Highlands, especially in northern Ferry County, recorded 4 to 6 inches of new snow accumulations in the early morning hours of January 12th.