Avalanche Forecast
Regions: Mt Hood.
Triggered avalanches are unlikely, but areas of shallow wet snow are expected, especially on steeper southerly facing slopes exposed to direct sunshine.
Detailed Forecast
Another dry, sunny and warm day is expected Wednesday. Freezing levels should again exceed 11,000 feet and along with light winds, causing areas of wet surface snow. Clearing overnight Tuesday should allow for the recent rain soaked upper snow layers to drain further, consolidate and allow for a thin surface crust to form.Â
While wet snow avalanches should be unlikely, some shallow surface wet snow may make it possible to initiate a small loose-wet slide on some steep, mostly southerly facing slopes during the warmest part of the day. Watch for areas where surface snow is becoming wet for more than the top few inches.
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Snowpack Discussion
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From 2 to over 3 inches of rain have fallen over the Mt Hood area from Sunday night to Monday evening, following about 5-10 inches of snowfall prior to the rain.Â
Few observations were received Monday or Tuesday, other than generally small wet slides, with Mt Hood Meadows patrol seeing evidence of larger wet slides at higher elevations above the forecasted terrain, near 9000 feet.
The rain should have released any recent snow received before the substantial warming arrived Sunday night. The rain has reached to the Cascade crest elevations to at least 7000 feet or higher, thus essentially resetting the snowpack. This recent rain should have eliminated any layers of concern in the upper snowpack, leaving behind wet or saturated upper snow layers.
We'll await more detailed impacts of the rain later in the week, as conditions will become more amenable to making observations.Â
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, West.
Elevations: All elevations.
Likelihood: Possible
Expected Size: 1 - 1