Avalanche conditions are steadily improving, however tomorrow will likely see a spike in temperatures. Be prepared for rapidly rising temperatures and related avalanche problems. Loose wet, cornices and touchier slabs are all problems if it warms up.
Confidence
Moderate - Intensity of incoming weather systems is uncertain
Weather Forecast
Mostly sunny skies tomorrow with a rising freezing level. The forecasted alpine high for the Spray region is -2. Using today as a reference, we can probably expect the actual high to beat that, especially on solar aspects. The winds will pick up to west/35km/hr.
Avalanche Summary
2 natural cornice avalanches were seen today. Details are:sz2-2.5, 2540m, N asp, traveled 200m vertical. Cornice fell from ridge onto slopes below and only triggered superficial slabs on the way down. No action from the Jan 6th.Sz 1.5, 2400m, N asp. Did not trigger slope belowLoose dry avalanches up to sz1.5 were noted on steep south alpine slopes today as well. Again, no triggering of slopes below.
Snowpack Summary
The cold clear nights have just started to put a layer of surface hoar down up to treeline. We can expect this to linger on north aspects, on south aspects the sun is making short work of melting it. The crusts from earlier in the week are still evident when breaking trail up to 1900m. Solar aspects will likely have a new crust from today's blue skies. Treeline has pockets of windslab left over from Feb 8th when we had the strong northerly wind event. Both of our problem layers (Feb 11th crust & Jan 6th facets) are repairing themselves and gaining strength. The alpine is currently a mess of wind slabs and thin breakable wind skins. Cornices have slowed in terms of growth, but there are some big ones out there!
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.
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.
Cornices
Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.