Avalanche Forecast

Archived

Jan 31st, 2015–Feb 1st, 2015

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Regions

Mt Hood.

Shallow storm slabs are possible, mainly on lee terrain near and above treeline later Sunday afternoon.

Detailed Forecast

An incoming frontal system will bring light rain and snow to the Mt. Hood area by Sunday afternoon. Snow levels should fluctuate around 5500 feet. New snow may bond poorly to surface crusts, allowing shallow storm slabs to develop especially on lee aspects near and above treeline.

Below treeline, light rain should have little impact on the avalanche danger.

A stronger system forecast for Monday will likely lead to increasing avalanche danger.

Snowpack Discussion

After last weekend's rain (Jan 24-25th), predominately mild or sunny weather settled in during the work week. No new avalanches have been reported over the last week.

The Meadows pro-patrol continues to report a strong surface crust and melt form layers in the upper snow pack this week.

Overall the snow pack at Mt Hood should predominately consist of stable consolidated rounded grains or melt form layers and crusts from warm periods so far this winter.

Problems

Storm Slabs

Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). 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.