A surface low pressure system off the Washington coast formed a stationary front draped across eastern Washington during the day of January 11th. A second low pressure formed along this front and migrated through eastern Washington and north Idaho. A rich plume of Pacific moisture enhanced into heavy wet snow across the Cascades and eastern Washington. Outside of the Cascades the heaviest snow accumulations were noted just to the north of the track of the low pressure and was largely confined to a 50 mile wide area across the northern Columbia Basin and the southern portions of the northern Washington mountain zones. Peripheral areas near the Canadian border and over the southern Columbia basin received generally 2 to 4 inches of snow from this system.

Heavy Snow in OKANOGAN HIGHLANDS, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 17:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

A spotter 12 miles south of Wauconda reported 4.0 inches of new snow accumulation.

Heavy Snow in SPOKANE AREA, WASHINGTON
From 11-JAN-18 07:00:00 to 11-JAN-18 19:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A spotter on the north side of Spokane measured 4.6 inches of new snow accumulation.

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

An observer near Clayton reported 6.5 inches of new snow accumulation.

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

An observer near Ford reported 5.0 inches of new snow accumulation.

Heavy Snow in SPOKANE AREA, WASHINGTON
From 11-JAN-18 07:00:00 to 11-JAN-18 19:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

An observer on Spokane's south hill reported 4.0 inches of new snow accumulation.

Heavy Snow in SPOKANE AREA, WASHINGTON
From 11-JAN-18 07:00:00 to 11-JAN-18 19:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

An observer in the Hangman Creek valley 5 miles south of Spokane reported 5.0 inches of new snow accumulation.

Heavy Snow in SPOKANE AREA, WASHINGTON
From 11-JAN-18 07:00:00 to 11-JAN-18 19:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

An observer 3 miles south of Veradale reported 5.0 inches of new snow accumulation.

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The 49 North ski area reported 13.0 inches of new snow from this storm system.

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The Mount Spokane ski area reported 7.5 inches of new snow from this storm system.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 17:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

The COOP observer at Holden Village reported 18.4 inches of new snow accumulation.

Heavy Snow in WENATCHEE AREA, WASHINGTON
From 11-JAN-18 05:00:00 to 11-JAN-18 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

An observer 4 miles south of Wenatchee reported 6.0 inches of new snow accumulation.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 17:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

The COOP observer at Leavenworth Fish Hatchery reported 11.0 inches of new snow accumulation.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 17:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

The COOP observer at Mazama reported 9.4 inches of new snow accumulation.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 17:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

The COOP observer at Plain reported 15.8 inches of new snow accumulation.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 17:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

An observer near Ardenvoir reported 10.4 inches of new snow accumulation.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 17:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

An observer 5 miles southwest of Peshastin reported 12.2 inches of new snow accumulation.

Heavy Snow in WENATCHEE AREA, WASHINGTON
From 11-JAN-18 05:00:00 to 11-JAN-18 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

An member of the public 5 miles southwest of Manson reported 12.0 inches of new snow accumulation.

Heavy Snow in WENATCHEE AREA, WASHINGTON
From 11-JAN-18 05:00:00 to 11-JAN-18 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

The Entiat Fish Hatchery reported 6.6 inches of new snow accumulation.

Heavy Snow in WATERVILLE PLATEAU, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 18:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

A member of the public in Mansfield reported 7.0 inches of new snow accumulation.

Heavy Snow in OKANOGAN HIGHLANDS, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 17:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

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

Heavy Snow in WATERVILLE PLATEAU, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 18:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

The COOP observer at Waterville reported 5.5 inches of new snow accumulation.

Heavy Snow in OKANOGAN VALLEY, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

A member of the public near Disautel reported 14.0 inches of new snow accumulation.

Heavy Snow in OKANOGAN VALLEY, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

The observer at Chief Joseph Dam reported 6.5 inches of new snow accumulation.

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

A member of the public 3 miles southeast of Loon Lake reported 5.3 inches of new snow accumulation.

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

A member of the public near Diamond Lake reported 6.0 inches of new snow accumulation.

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A spotter near Loon Lake reported 5.5 inches of new snow accumulation.

Heavy Snow in SPOKANE AREA, WASHINGTON
From 11-JAN-18 07:00:00 to 11-JAN-18 19:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

The observer at the NWS Spokane WFO measured 7.7 inches of new snow accumulation.

Heavy Snow in SPOKANE AREA, WASHINGTON
From 11-JAN-18 07:00:00 to 11-JAN-18 19:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

The observer at the Spokane International Airport measured 6.3 inches of new snow accumulation.

Heavy Snow in SPOKANE AREA, WASHINGTON
From 11-JAN-18 07:00:00 to 11-JAN-18 19:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

The observer at the Spokane International Airport measured 6.3 inches of new snow accumulation.

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A member of the public near Colville reported 4.5 inches of new snow accumulation.

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A member of the public near Colville reported 4.5 inches of new snow accumulation.

Heavy Snow in OKANOGAN HIGHLANDS, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 17:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

A member of the public near Malo reported 8.0 inches of new snow accumulation.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 17:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

A member of the public near Telma reported 16.0 inches of new snow accumulation.

Heavy Snow in WENATCHEE AREA, WASHINGTON
From 11-JAN-18 05:00:00 to 11-JAN-18 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

An member of the public in East Wenatchee reported 5.8 inches of new snow accumulation.

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

A member of the public near Usk reported 5.5 inches of new snow accumulation.

Heavy Snow in SPOKANE AREA, WASHINGTON
From 11-JAN-18 07:00:00 to 11-JAN-18 19:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A member of the public near 5 mile reported 5.8 inches of new snow accumulation.

Heavy Snow in OKANOGAN VALLEY, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

A member of the public near Omak reported 4.5 inches of new snow accumulation.

Heavy Snow in OKANOGAN VALLEY, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A spotter near Okanogan reported 4.5 inches of new snow accumulation.

Heavy Snow in OKANOGAN VALLEY, WASHINGTON
From 11-JAN-18 06:00:00 to 11-JAN-18 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A spotter near Brewster reported 7.0 inches of new snow accumulation.