Watch for warm temperatures and potentially some heavy precip this week. Remember, even small amounts of solar heating or rain can weaken snow quickly to cause an increase in the avalanche hazard beyond the posted danger ratings.
Weather Forecast
Watch for moderate warming on Monday with a freezing level to 2700m and a few showers in the forecast. A poor recovery into Tuesday will allow further shower activity to weaken the snowpack further at lower elevations. Models are conflicted so far for Wednesday but we may see heavy precip. Watch freezing levels and precip amounts carefully.
Snowpack Summary
10 to 40 cm of snow now lies on the April 11 crust that is found on N aspects to 2300m and to ridgelines on solar aspects. Moist snow below 1800m on all aspects. The deeply buried February Facets and early season Basal Facets remain weak and will likely wake up with significant and sustained heating.
Avalanche Summary
Widespread Loose Wet activity has been seen with rain soaked snow below 2000m. These events have been up to size 1.5 running 10 to 20 cm deep over the April 11 crust on all aspects below about 2200m.
Confidence
Timing, track, or intensity of incoming weather system is uncertain on Wednesday
Problems
Loose Wet
Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.
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.
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.