Avalanche Forecast
Regions: Mt Hood.
Use normal caution and don't get a sunburn at Mt Hood on Monday.
Detailed Forecast
Frontal moisture should mostly lift north to BC  Sunday night to Monday afternoon. Fair weather should be seen Monday at Mt Hood with warmer temperatures.
Recent snow and wet snow has had a chance to slightly consolidate and mostly stabilize at Mt Hood. Possible loose wet avalanche should be the main problem in most of this area and will be emphasized on solar slopes but watch for loose wet conditions on all aspects.
Older shallow wind slab may linger on previous lee slopes. Watch for possible firmer previously wind transported snow mainly on north to east aspects.
Cornices won't be listed as an avalanche problem. But avoid slopes below cornices and ridges or summits where cornices may be hard to see in all areas.
Snowpack problems west of the crest and Mt Hood for the time being should be in the upper or surface layers. The mid and lower snowpack west of the crest consists of layers of stable consolidated rounded grains or melt forms and crusts from multiple warm periods this winter. Many areas at the lowest elevations do not have enough snow to cause an avalanche danger.
Snowpack Discussion
Winter made a bit of a comeback in the Northwest in mid to late March. Several storms or storm cycles brought heavy snow to the above treeline areas west of the crest especially on the volcanoes.
A warm front caused pretty heavy rain mainly west of the crest Wednesday to Thursday morning. This caused an avalanche cycle and consolidation west of the crest with the most avalanches at Mt Rainier.
A vigorous front and short wave crossed the Northwest Friday night causing strong west-southwest winds, some rain and snow and lowering snow levels. Snow levels lowered enough by Saturday to cause up to 2-3 inches of snowfall at higher NWAC stations west of the crest including at Mt Hood and likely a few more inches at higher elevations. The Meadows patrol found some isolated shallow wind slab on Saturday on northeast slopes above 6500 feet.
Frontal moisture is moving mainly to BC Sunday and there is quite a difference in the weather from north to south. Fair weather is being seen at Mt Hood on Sunday. The Meadows patrol found generally stable conditions today.
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Avalanche Problems
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: Alpine, Treeline.
Likelihood: Possible
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.
Elevations: Alpine.
Likelihood: Possible
Expected Size: 1 - 1