Warmth remains the primary driver of avalanche hazard as we shift into a more spring like pattern. Minimize your exposure to large slopes if the snowpack is becoming moist or wet.
Weather Forecast
MONDAY: Freezing level starting at valley bottom, rising to 1600m. Light variable winds at all elevations. No significant precipitation expected. Broken cloud cover.TUESDAY: Freezing level starting at 700m, rising to 1800m. Light variable winds at all elevations. No significant precipitation expected. Skies clearing in the afternoon.WEDNESDAY: Freezing level starting at 1000m, rising to 2000m. Light N/NE winds at all elevations. No significant precipitation expected. Clear skies.
Avalanche Summary
On Saturday storm slabs ran to size 1.5 on NE through NW facing features between 1900 and 2700m. Loose dry avalanches to size 1.5 were reported from all aspects between 2000 and 2500m. A few size wet slabs were reported from southerly facing features between 2100 and 2500m. There were a couple noteworthy avalanches from last week. On Thursday a rider was partially buried in a size 2.5 wind slab on a north aspect at 2600m. On Wednesday, a naturally-triggered size 2.5 wind slab was observed on a NE aspect at 2500m. On that same day an ice fall triggered a size 3 deep persistent slab which failed at ground.
Snowpack Summary
Up to 20cm of dry snow may be hiding previously formed wind slabs on upper elevation slopes. These overlie a crust which varies in thickness with elevation. Sun may destabilize new snow and cornices. Below about 2000 m, loose moist snow makes up much of the snowpack underneath a surface crust. Persistent weak layers in the upper snowpack remain a lingering concern. The mid-March crust/facet layer is down around 60 cm. Down around 80 cm is the mid-February crust/facet/surface hoar layer. Both of these layers are slowly improving in strength, although it may still be possible to trigger one of these, causing a very large avalanche.
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.
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.