The change to MOD at treeline reflects the improving trend with the Feb 11th layer. Keep in mind, at MOD, human triggering is still possible in specific areas. Safe travel still requires attention and good use of terrain.
Weather Forecast
Overnight lows will reach -16. A mix of sun and cloud for tomorrow. Alpine highs will be around -3 with steady west winds reaching 25km/hr. The freezing level will approach valley bottom.
Avalanche Summary
Nothing new today.
Snowpack Summary
Below treeline is still a blend of crusts and newer snow. Travel is reasonable with ski penetrations of 20-30cm in untracked terrain. The snowpack has continued to improve at the treeline elevation. Today's investigation had a hard windslab on east aspects down 40cm. The bond with the underlying snow appeared to be quite good, but given the current variability, it is a hard put a lot of weight on the test results. This slab was limited to exposed areas and is thought to be left over from the reverse loading event from Feb 8. The alpine is still soft wind slab mixed in with hard slabs. Cornices are on all aspects and in some cases, quite large and intimidating.
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.