Avalanche Forecast
Regions: Mt Hood.
High danger now expected on Sunday at Mt Hood.
Detailed Forecast
Northwest winds and heavy snow is being seen at Mt Hood on Sunday.About 15 inches of storm snow has accumulated since the storm began yesterday.Snow is much heavier at Mt Hood Sunday than the rest of the forecast area.
With these snowfall and loading rates new storm and wind slab is certain on Sunday. Back country travel in avalanche terrain is not recommended especially in the near and above treeline on Sunday. The surface hoar will increase instability where it gets buried intact.
It will also take longer for some stabilizing at Mt Hood than the rest of the forecast area since stronger winds and heavier snowfall should last longer there on Sunday.
Snowpack Discussion
A cooler period with little precipitation was seen about Thursday to Friday. Some skiers were reporting better conditions on lower angle slopes with skis scraping crusts on some steeper slopes. Surface hoar is possible from Thursday night.
 A cold front is moving over the Northwest on Saturday and Saturday night causing west winds and moderate to heavy snow and snow showers and a cooling trend. This should build some new wind and storm slab especially at Mt Hood by Sunday.
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Avalanche Problems
Storm Slabs
Release of a soft cohesive layer (a slab) of new snow that breaks within the storm snow or on the old snow surface. Storm-slab problems typically last between a few hours and few days. Storm-slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
You can reduce your risk from Storm Slabs by waiting a day or two after a storm before venturing into steep terrain. Storm slabs are most dangerous on slopes with terrain traps, such as timber, gullies, over cliffs, or terrain features that make it difficult for a rider to escape off the side.
Storm slabs usually stabilize within a few days, and release at or below the trigger point. They exist throughout the terrain, and can be avoided by waiting for the storm snow to stabilize.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Very Likely
Expected Size: 1 - 1
Wind Slabs
Release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
Wind Slabs form in specific areas, and are confined to lee and cross-loaded terrain features. They can be avoided by sticking to sheltered or wind-scoured areas..
Wind Slab avalanche. Winds blew from left to right. The area above the ridge has been scoured, and the snow drifted into a wind slab on the slope below.
Wind slabs can take up to a week to stabilize. They are confined to lee and cross-loaded terrain features and can be avoided by sticking to sheltered or wind scoured areas.
Aspects: North, North East, East, South East, South.
Elevations: All elevations.
Likelihood: Very Likely
Expected Size: 1 - 1