Solar radiation this morning is expected to be cut out by cloud cover but a thin layer of cloud could increase the solar affect. Manage your groups exposure to overhead hazard accordingly.
Weather Forecast
Weakening ridge of high pressure over the interior will mean increasing cloudiness today. No precipitation is expected until Tuesday night when a Pacific system makes it way over to us. Light to moderate amounts are expected then with rising freezing levels,.
Snowpack Summary
The upper snowpack will vary depending on aspect. North and east will have settling snow, south and west will have the Mar 22 crust down 10cm. The Mar 13 crust down 45-65 and the March 2 CR/SH layer down 1m. Tests show hard sudden result on the Mar 2 layer, propagation tests still show large potential for propagation. The Feb10 layer is down ~2m.
Avalanche Summary
No new avalanches yesterday observed or reported in the park yesterday. On Friday a size 3.5 natural avalanche released in Grizzly Bowl, SE asp, ~2600m, presumably from a cornice trigger. These sporadic events keep our guard up.
Confidence
Intensity of incoming weather systems is uncertain on Wednesday
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.
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.
Deep Persistent Slabs
Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.