Avalanche Forecast
Regions: Mt Hood.
A transition from the recent wet warm weather to dry warm weather will begin on Tuesday. You will need to watch for a variety of snow and avalanche conditions on Tuesday.
Detailed Forecast
The upper ridge will begin to rebuild over the west US on Tuesday. At Mt Hood this should cause decreasing west winds with light showers decreasing Tuesday morning and ending Tuesday afternoon.
New wind slab from the storm on Monday maybe found mainly on steep NW to E slopes near ridges above treeline. Watch for firmer wind transported snow.
New storm slab seems possible where there is more than a few inches of snowfall in areas with light wind.
Any cooling will be limited Tuesday morning and temperatures will be on the rise again by Tuesday afternoon. More mostly small loose wet avalanches may be seen on steep mainly solar slopes.
As a result of the unseasonably low snowpack, especially at lower elevations, watch for terrain hazards such as open creeks, partially covered rocks and vegetation.
Snowpack Discussion
A series of fronts in an atmospheric river has been crossing the Northwest. Mt Hood has seen about 2 inches of WE mostly as rain from about February 5th-10th with about 10-12 inches of melting, consolidation and stabilizing of the snowpack.
No avalanches were seen or reported by the Mt Hood Meadows pro-patrol through Sunday afternoon with recent wet snow well bonded and not causing any significant loose wet problems near and below treeline.
But a filling low pressure system is crossing  mainly the south Cascades and Mt Hood area on Monday. This is causing the most wind and rain or snow in the far south Cascades and at Mt Hood on Monday. A brief minor drop in snow levels should be seen at Mt Hood Tuesday morning.
The mid and lower snowpack at Mt Hood should consist of layers of stable consolidated rounded grains or melt forms and crusts from multiple warm periods this winter.
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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, North West.
Elevations: Alpine, Treeline.
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: All elevations.
Likelihood: Possible
Expected Size: 1 - 1
Loose Wet
Release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. They generally move slowly, but can contain enough mass to cause significant damage to trees, cars or buildings. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.
Travel when the snow surface is colder and stronger. Plan your trips to avoid crossing on or under very steep slopes in the afternoon. Move to colder, shadier slopes once the snow surface turns slushly. Avoid steep, sunlit slopes above terrain traps, cliffs areas and long sustained steep pitches.
Several loose wet avalanches, and lots of pinwheels and roller balls.
Loose wet avalanches occur where water is running through the snowpack, and release at or below the trigger point. Avoid terrain traps such as cliffs, gullies, or tree wells. Exit avalanche terrain when you see pinwheels, roller balls, a slushy surface, or during rain-on-snow events.
Aspects: South East, South, South West.
Elevations: All elevations.
Likelihood: Possible
Expected Size: 1 - 1