During the day of December 11th a moist warm front developed over eastern Washington. The mountains and valleys of northeast Washington received heavy snow from this system, although the southern valleys switched over to rain late in the day. This storm brought light to moderate accumulations of heavy wet snow to the northern Columbia Basin as well but amounts were limited to terrain above 2000 feet elevation where 1 to locally 3 inches fell before snow changed over to rain in the evening as the warm front passed through. This change-over created very hazardous road conditions in the northern Columbia Basin, claiming the life of one motorist.

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 11-DEC-18 07:00:00 to 11-DEC-18 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

A member of the public near Northport reported 4.0 inches of snow accumulation from this storm.

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 11-DEC-18 07:00:00 to 11-DEC-18 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The 49 North ski resort recorded 9.0 inches of new snow with this storm system.

Heavy Snow in OKANOGAN VALLEY, WASHINGTON
From 11-DEC-18 05:00:00 to 11-DEC-18 15:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

A member of the public at Omak reported 4.0 inches of snow accumulation.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 11-DEC-18 03:00:00 to 11-DEC-18 19:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

An observer near Plain reported 15.5 inches of new snow accumulation from this storm. The COOP observer 2 miles north of Plain reported 9.2 inches of snow accumulation.

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 11-DEC-18 07:00:00 to 11-DEC-18 16:00:00 (PST-8)
Property damage: 0.25K
Crop damage: 0.00K
Reported by: Trained Spotter

A spotter near Deer Park reported 4.5 inches of new snow accumulation. The snow was very wet and heavy, breaking tree branches with one of the branches smashing a window on a house.

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 11-DEC-18 07:00:00 to 11-DEC-18 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

The COOP observer at Colville reported 4.0 inches of snow from this storm.

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 11-DEC-18 07:00:00 to 11-DEC-18 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

An observer near Clayton recorded 6.0 inches of snow accumulation from this storm.

Winter Weather in NORTHEAST MOUNTAINS, WASHINGTON
From 11-DEC-18 15:00:00 to 11-DEC-18 16:00:00 (PST-8)
Property damage: 60.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Local media reported a highway fatality (indirect) when a car spun on an icy road, crossed the median into the oncoming lane and struck another car. The roads in the area were reported as very icy.

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 11-DEC-18 07:00:00 to 11-DEC-18 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

An observer near Elk recorded 4.0 inches of snow accumulation from this storm.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 11-DEC-18 03:00:00 to 11-DEC-18 19:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A member of the public near Lake Wenatchee reported 30.0 inches of storm total snow with this weather system.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 11-DEC-18 03:00:00 to 11-DEC-18 19:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

The COOP observer at Mazama reported 9.2 inches of new snow with this storm.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 11-DEC-18 03:00:00 to 11-DEC-18 19:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

The COOP observer at Stehekin reported 30.0 inches of new snow with this storm.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 11-DEC-18 03:00:00 to 11-DEC-18 19:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

The COOP observer at Holden Village reported 20.0 inches of new snow with this storm.

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 11-DEC-18 07:00:00 to 11-DEC-18 16:00:00 (PST-8)
Property damage: 0.25K
Crop damage: 0.00K
Reported by: COOP Observer

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

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 11-DEC-18 07:00:00 to 11-DEC-18 16:00:00 (PST-8)
Property damage: 0.25K
Crop damage: 0.00K
Reported by: CoCoRaHS

An observer at Sacheen Lake reported 7.4 inches of new snow.

Heavy Snow in EAST SLOPES NORTHERN CASCADES, WASHINGTON
From 11-DEC-18 03:00:00 to 11-DEC-18 19:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: SNOTEL

The Pope Ridge SNOTEL site recorded 10.0 inches of snow accumulation.

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 11-DEC-18 07:00:00 to 11-DEC-18 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

A member of the public near Marcus reported 5.0 inches of snow accumulation from this storm.

Heavy Snow in NORTHEAST MOUNTAINS, WASHINGTON
From 11-DEC-18 07:00:00 to 11-DEC-18 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

A member of the public at Tum Tum reported 4.0 inches of snow accumulation from this storm.