Regions
Northwest Inland.
Confidence
Poor - Due to limited field observations
Weather Forecast
Synopsis: The pattern calms down a bit becoming drier and colder, although most of the Arctic Air should flush out by Sunday.Saturday: Freezing Level: 500m Precip: 2-4mm/4-8cm Wind: W, Light gusting Moderate+.Sunday: Freezing Level: Surface Precip: trace Wind: NW, LightMonday: Freezing Level: 400m Precip: 3-5mm/6-10cm Wind: SE, Light
Avalanche Summary
No avalanches were reported on Thursday from the region. In the neighboring Northwest Coastal region a bit of sluffing from steep terrain was reported Thursday along with a natural size 1 avalanche from a wind loaded pocket below a small cornice that failed on the March 9th surface hoar. In the southern portion of the region a couple large glide slabs failed resulting in large (size 3) avalanches.
Snowpack Summary
20 - 40cm of unconsolidated storm snow rests on the old/new snow interface. Prior to this last storm, the surface was a mix of crusts, old wind slabs and fairly widespread large surface hoar (which we're calling the March 9th surface hoar). Professionals in the region are keeping their eyes on this layer and testing produces sudden collapse failures at this interface. In many places, the storm snow has not yet taken on any slab characteristics, but there are no doubt some locations where the storm snow has been massaged into a more cohesive slab. As a result the current slab problem is "pockety" in nature. You'll need to dig down to the old surface and test it to get a feel for what's happening in your particular drainage. The mid snowpack is generally well settled and strong.
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.