Cooling temperatures over the next 72 hours will reduce the avalanche danger as the freezing level drops.
Weather Forecast
A drier and colder air mass is forecast to arrive on Wednesday. Freezing levels will fall to the valley bottom resulting in overnight freezing. Winds will be moderate from the west and south west. Snow is expected on Friday in townsite area.
Snowpack Summary
Over the past 24 hours precipitation has fallen as rain below 2,400m. At treeline, the heavier snow sits over a persistent weak layer dating to Dec 20th. Below treeline, isothermic conditions exist.
Avalanche Summary
Avalanche control, at and above treeline, produced numerous slab avalanches up to size 3 along the icefield parkway. At times the avalanche was triggered before the explosives detonated. Below 1,800m moist point release to size 2 are traveling to mid runout. and taking the snowpack to ground.
Confidence
Freezing levels are uncertain on Wednesday
Problems
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.
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.
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.