Avalanche Forecast
Regions: Mt Hood.
The storm over the region Saturday night and Sunday produced mainly rain for the Mt. Hood area at elevations where avalanche forecasts apply. However, the avalanche danger on the upper volcano will likely be much greater due to heavy snow and strong winds. Travel into the alpine is strongly discouraged.
Detailed Forecast
The storm over the weekend should be in the rear view mirror by Monday, as high pressure rebuilds.  This should cause light to moderate northwest crest level winds and little if any accumulation of new snow.Â
Recent storm and wind slabs should persist at higher elevations, especially above treeline and near ridgetops. Best performing numerous quick test pits or pole tests to determine recent snow conditions. Wet snow conditions should gradually drain Monday at mid and lower elevations.Â
Snowpack Discussion
The snowpack on Mt. Hood below 6000' remains relatively shallow and marginal for avalanche formation.  Snowdepths are now 1-2 ft after snowfall Saturday at NWAC stations near tree-line.  We have no recent avalanche activity or observations which, considering the strength of the weekend storm is a good thing!
A very strong storm began affecting the Mt Hood area Friday. Â NWAC weather stations have recorded between 5-10" of water equivalent in 48 hours as of Sunday evening! Â The majority of this has been in the form of rain, however, above treeline much of the recent precipitation has been snow. Â Coupled with winds in excesses of 100 mph, there is no doubt highly varied conditions on Mt Hood presently.
The rain, snow, extreme winds and fluctuating freezing levels have certainly changed the landscape of the snow conditions by Sunday.  Little field information has been available Sunday, however, expect lower to mid elevations to begin slowly freezing and forming a new crust with shallow amounts of new snow being well bonded to the old surface.
Be extremely cautious venturing to higher elevations as deep storm and wind slabs are likely.
Â
Â
Avalanche Problems
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.
Elevations: Alpine.
Likelihood: Likely
Expected Size: 1 - 1
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: Alpine.
Likelihood: Likely
Expected Size: 1 - 1