Avalanche Forecast

Archived

Feb 13th, 2018–Feb 14th, 2018

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Regions

Olympics.

Watch for fresh and shallow new wind slabs on lee slopes near and above treeline Wednesday. Avoid steep slopes with wind deposited snow such as below cornices, on wind drifts, and near uneven snow surfaces. In areas where shallow loose new snow bonds poorly to the underlying crust, avoid steep icy slopes where it will be difficult to stop a fall.

Detailed Forecast

A quick moving frontal system should bring fresh snowfall to Hurricane Ridge Tuesday night and Wednesday morning along with much cooler temperatures. Several inches of new snow may bond poorly to a medley of surface crusts, but new snowfall should not be significant enough to present a storm slab problem.

While winds are not forecast to be especially strong with this system, winds may build fresh and shallow new wind slabs on lee slopes near and above treeline. Avoid steep slopes with wind deposited snow such as below cornices, on wind drifts, and near uneven snow surfaces.

In areas where shallow loose new snow bonds poorly to the underlying crust, avoid steep icy slopes where it will be difficult to stop a fall.

Snowpack Discussion

A strong well consolidated snowpack exist in most locations in the Olympics. Recent colder temperatures have allowed surface snow to freeze creating a supportable surface crust. On slopes receiving direct sun, this surface crust softens during the day and re-freezes at night.

Warm and wet weather the first week of February has created a spring-like and relatively uniform snowpack. No layers of concern exist in the snowpack at this time.

Observations

No recent observations.

Problems

Wind Slabs

Wind Slab avalanches are the 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.