Avalanche Forecast

Another round of precipitation and winds will reach the Cascades during the day Sunday. Avalanche conditions should deteriorate as the storm moves through the area. Slightly higher precipitation amounts and winds should lead to a slightly elevated avalanche danger in the Crystal and Paradise areas.

Expect winds to transport snow and form new sensitive wind slabs on exposed terrain features near and above treeline. Watch for an increase in wind speed and visual signs of winds actively transporting snow such as plumes and newly forming cornices. As wind transportation increases through the day, identify and avoid areas where winds are depositing snow.

Small shallow storm slabs will develop on Sunday during period of higher precipitation intensity. Lingering storm slabs formed throughout the storm period are gaining strength but may be found in in isolated locations. These older storm slabs are most likely to trigger in steep terrain, on convex rolls, and on unsupported slopes. As storm slabs grow consider the consequences of the terrain where being caught in even a small avalanche may have more drastic consequences such as above cliffs, gullies, and open creeks.

A stormy period beginning Wednesday has brought 12-18 inches of storm snow to the Passes and 6-12 inches in the Paradise/Crystal areas. A general cooling trend throughout the storm period created a generally strong bond to the most recent crust layer.

Moderate to strong southwest winds redistributed the new snow creating a variety of snow surfaces near and above treeline. Wind slabs have been observed on several aspects in exposed terrain especially along ridgelines.

Observations indicate recent snow is bonding well to the 1/16 crust.

Observations

Central

A public observation from Jim Hill on Saturday reported an avalanche triggered by cornice fall on a near treeline N-facing slope.

NWAC Pro Observer Jeremy Allyn was in the Snoqualmie Pass area Friday and Saturday. On Saturday Jeremy observed 18 inches of recent snow over the 1/16 crust layer. Wind transportation was limited to exposed ridgeline terrain features. No new avalanches were observed.

Several avalanche professionals throughout the Snoqualmie Pass area Saturday reported 12-15 inches of generally right-side-up storm snow well bonded to the 1/16 crust. Only small loose dry avalanches were observed.

South

On Friday, NWAC forecaster Dallas Glass traveled in the Crystal Mountain backcountry. The recent winds have caused highly variable storm snow conditions with exposed areas striped of recent snow. New snow was observed to be generally well bonded to the 1/18 crust. 

Pro Patrol at Crystal Mountain Thursday morning reported shallow 2-4" very soft slabs. The underlying rain crusts have become very firm by Thursday morning above 6000 ft and gradually softer at lower elevations.