A stationary front fed by a rich plume of Pacific moisture followed by the passage of a weakening surface low pressure brought heavy snow to the mountains and northern Columbia Basin of eastern Washington beginning on the 28th of December and continuing into the 30th. As the low pressure approached the stationary front moved north slightly and produced pockets of freezing rain in the western  Columbia Basin and the Spokane area. Heavy rain occurred south of the front over the Palouse region where Pullman received 2.24 inches of rain during this storm.  The warm front never migrated into the northeast mountains and these mountains and valleys received heavy snow until the storm ended.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 28-DEC-17 10:00:00 to 30-DEC-17 04:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

The Holden Village COOP observer reported 24.7 inches of storm total new snow.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 28-DEC-17 10:00:00 to 30-DEC-17 04:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

The Plain COOP observer reported 13.1 inches of new snow.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 28-DEC-17 10:00:00 to 30-DEC-17 04:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

The Mazama COOP observer reported 14.0 inches of new snow.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 28-DEC-17 10:00:00 to 30-DEC-17 04:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

An observer near Plain reported 12.4 inches of new snow.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 28-DEC-17 10:00:00 to 30-DEC-17 04:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

An observer in Leavenworth reported 11.0 inches of new snow.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 28-DEC-17 10:00:00 to 30-DEC-17 04:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A spotter near Ardenvoir reported 7.5 inches of new snow.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 28-DEC-17 10:00:00 to 30-DEC-17 04:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

A spotter near Winthrop reported 9.0 inches of new snow.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 28-DEC-17 10:00:00 to 30-DEC-17 04:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

A citizen near Telma reported 32.0 inches of storm total new snow.

Heavy Snow in OKANOGAN HIGHLANDS, WASHINGTON
From 29-DEC-17 12:00:00 to 30-DEC-17 05:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

The observer at Boundary Dam reported 4.5 inches of new snow.

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 29-DEC-17 12:00:00 to 30-DEC-17 05:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A spotter 8 miles southeast of Northport reported 11.5 inches of new snow.

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 29-DEC-17 12:00:00 to 30-DEC-17 05:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

A citizen near Arden reported 5.3 inches of new snow.

Heavy Snow in OKANOGAN HIGHLANDS, WASHINGTON
From 29-DEC-17 12:00:00 to 30-DEC-17 05:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

A citizen 1 miles north of Republic reported 7.0 inches of new snow.

Heavy Snow in OKANOGAN HIGHLANDS, WASHINGTON
From 29-DEC-17 12:00:00 to 30-DEC-17 05:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

An observer near Malo reported 6.0 inches of new snow.

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 29-DEC-17 12:00:00 to 30-DEC-17 05:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

A citizen near Orient reported 5.0 inches of new snow.

Heavy Snow in SPOKANE AREA, WASHINGTON
From 29-DEC-17 05:00:00 to 30-DEC-17 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

A citizen near Newman Lake reported 6.0 inches of new snow.

Heavy Snow in SPOKANE AREA, WASHINGTON
From 29-DEC-17 05:00:00 to 30-DEC-17 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

An observer in north Spokane reported 5.0 inches of new snow.

Heavy Snow in OKANOGAN HIGHLANDS, WASHINGTON
From 29-DEC-17 12:00:00 to 30-DEC-17 05:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

An observer 8 miles northeast of Republic reported 5.9 inches of new snow.

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 29-DEC-17 12:00:00 to 30-DEC-17 05:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

An observer near Clayton reported 4.0 inches of new snow. As the storm ended snow turned to freezing rain with a citizen on social media reporting 0.5 inches of ice accumulation.

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 29-DEC-17 12:00:00 to 30-DEC-17 05:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

A citizen near Usk reported 5.0 inches of new snow.

Heavy Snow in SPOKANE AREA, WASHINGTON
From 29-DEC-17 05:00:00 to 30-DEC-17 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

A citizen in Spokane Valley reported 7.0 inches of new snow. Light accumulations of ice from freezing rain occurred as the storm ended.

Heavy Snow in SPOKANE AREA, WASHINGTON
From 29-DEC-17 05:00:00 to 30-DEC-17 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

An observer near Veradale reported 3.5 inches of new snow. As the storm ended light accumulations of ice from freezing rain occurred.