Northwest Avalanche Bulletin

This information is issued by the NW Avalanche Center, a federal agency in Seattle, WA.

Northwest Weather and Avalanche Center Advisory

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Avalanche Forecast - WA Cascades, Olympics

OLYMPICS

WASHINGTON CASCADES NEAR AND WEST OF THE CREST

Sunday: Considerable avalanche danger above 5000 feet and moderate below, slightly increasing during the afternoon.

Monday: Considerable avalanche danger above 5 to 6000 feet and moderate below, increasing during the late morning and afternoon, mainly sun exposed slopes.

WASHINGTON CASCADES EAST OF THE CREST

Sunday: Considerable avalanche danger above 5 to 6000 feet and moderate below, slightly increasing during the afternoon.

Monday: Considerable avalanche danger above 6000 feet and moderate below, increasing during the late morning and afternoon, mainly sun exposed slopes.

Snowpack Synopsis

A cooling trend and diminishing snowfall has occurred from late Friday to Sunday morning. This has allowed for a decreasing trend in the avalanche danger as unstable layers continue to stabilize.

A significant storm cycle and subsequent avalanche cycle occurred Thursday and Friday with further avalanches reported Saturday, mainly in the Olympics. The most recent storm deposited 1 to 3 feet of snow with the greatest snowfall received on the volcanoes. The storm came with warming temperatures and very strong winds, depositing unstable slab layers over existing weak snow. This structure lead to very unstable conditions with widespread natural and triggered avalanches reported in the Olympics and both west and east sides of the Cascade crest.

Some consolidation has occurred along with cooling and decreasing winds since late Friday helping to lower the danger, however lingering unstable layers should persist on previously wind load slopes, mainly northerly facing at higher elevations, especially near ridges.

Backcountry travelers should continue to travel in a cautious mode and practice safe travel techniques while performing snow stability tests as local conditions can vary significantly.

Sunday and Sunday night

A front is expected to approach the coast and stall late Sunday. This should cause increasing high clouds over most areas, with a chance of a light rain or snow over the Olympics along with increasing winds and a warming trend. A warming trend is expected in the Cascades as well under filtered sunshine. The sunshine and warming may cause an increase in danger on sun exposed slopes as recent new snow becomes increasingly wet and weak. Watch for snowballing and the beginnings of wet snow instability as snow begins to melt and release from trees and cliffs, possibly releasing slides on slopes below.

Lingering unstable layers may persist on steep northwest to northeast facing slopes, mainly at higher elevations where triggered avalanches remain likely.

Monday and Monday night

Further warming with moderate risge top winds and filtered sunshine is expected Monday. This should again cause a gradual increase in danger late morning and afternoon as surface snow becomes increasingly wet, mainly on southerly facing slopes.

Backcountry travelers are urged to conitnue to use caution in steeper terrian at higher elevations as some previously deposited unstable layers may persist.

Avalanche Forecast - Mt Hood

MT HOOD

Sunday: Considerable avalanche danger above 5 to 6000 feet and moderate below, slightly increasing during the afternoon.

Monday: Considerable avalanche danger above 6000 feet and moderate below, increasing during the late morning and afternoon, mainly sun exposed slopes.

Snowpack Synopsis

A cooling trend and diminishing snowfall has occurred from late Friday to Sunday morning. This has allowed for a decreasing trend in the avalanche danger as unstable layers continue to stabilize.

A significant storm cycle and subsequent avalanche cycle occurred Thursday and Friday with further avalanches reported Saturday. The most recent storm deposited 1 to 2 feet of snow in the Mt Hood area through Saturday morning, with another 1 to 2 inches by Sunday morning. The storm came with warming temperatures and very strong winds, depositing unstable slab layers over existing weak snow. This structure lead to very unstable conditions with widespread natural and triggered avalanches reported in the Mt Hood area.

Some consolidation has occurred along with cooling and decreasing winds since late Friday helping to lower the danger, however lingering unstable layers should persist on previously wind load slopes, mainly northerly facing at higher elevations, especially near ridges.

Backcountry travelers should continue to travel in a cautious mode and practice safe travel techniques while performing snow stability tests as local conditions can vary significantly.

Sunday and Sunday night

A front is expected to approach the coast and stall late Sunday. This should cause increasing high clouds over Mt Hood along with increasing winds and a warming trend. The sunshine and warming may cause an increase in danger on sun exposed slopes as recent new snow becomes increasingly wet and weak. Watch for snowballing and the beginnings of wet snow instability as snow begins to melt and release from trees and cliffs, possibly releasing slides on slopes below.

Lingering unstable layers may persist on steep northwest to northeast facing slopes, mainly at higher elevations where triggered avalanches remain likely.

Monday and Monday night

Further warming with moderate risge top winds and filtered sunshine is expected Monday. This should again cause a gradual increase in danger late morning and afternoon as surface snow becomes increasingly wet, mainly on southerly facing slopes.

Backcountry travelers are urged to conitnue to use caution in steeper terrian at higher elevations as some previously deposited unstable layers may persist.

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