Avalanche Forecast

Archived

Jan 6th, 2015–Jan 7th, 2015

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Regions

Mt Hood.

Areas of wet snow are expected, especially on steeper southerly facing slopes exposed to direct sunshine.

Detailed Forecast

Drying, clearing and very warm air with freezing levels nearing 12,000 feet are expected Tuesday. This should allow for the recent rain soaked upper snow layers to drain and gradually consolidate. Clearing overnight Monday may have allowed for radiational cooling to form a thin melt-freeze crust.

Snowpack Discussion

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.

Few observations were received Monday, other than reports of creek beds opening and water falls spilling to the valley floors!

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.

Problems

Loose Wet

Loose Wet avalanches are the 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. 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.