Avalanche Forecast
Issued: Jan 18th, 2014 9:06AM
The alpine rating is Deep Persistent Slabs and Wind Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Fair
Weather Forecast
A ridge of high pressure will continue to dominate the region for the forecast period bringing dry conditions, mainly sunny skies and light winds from the west/northwest. Freezing levels should hover around 1000m for Sunday. Although there's a possibility of an inversion redeveloping for Monday and Tuesday, alpine temperatures are expected to remain just below freezing. No significant precipitation is expected for at least a week.
Avalanche Summary
On Friday explosives avalanche control produced at least 3 size 3 slab avalanches which failed to ground in steeper alpine terrain. 2 size 3, and 1 size 3.5 natural slab avalanches were also noted. At least 2 of these failed at ground level. All avalanches observed failed on a variety of aspects. No avalanche reports from Saturday's warm-up were available at the time of publishing this bulletin.
Snowpack Summary
Between 60cm and 90cm of well settled storm snow exists as a stubborn hard wind slab in many exposed areas. Steep, sun exposed slopes are seeing a daily melt-freeze cycle while surface hoar has been growing in some shaded terrain. Below the recently formed storm slab you may find surface hoar buried around January 8th, although no recent avalanche reports have been attributed to this layer. In the mid to lower pack you may find a surface hoar layer buried in mid December. Further down you may also find the December facet/crust combo. These layers are likely gaining strength, but professional operators are treating them with caution.The biggest concern throughout the region is a layer of weak sugary depth hoar at the base of the snowpack which may coexist with a crust which formed in October. I would continue to be suspicious of any large or unsupported upper elevation slopes, especially if they haven't already avalanched. Possible triggers include a heavy load over a thin spot, a cornice fall or rapid temperature change. Any avalanche failing at this interface would be highly destructive.
Problems
Deep Persistent Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Wind Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Jan 19th, 2014 2:00PM