Lizard-Flathead

Human triggering of large persistent slab avalanches remains possible; especially on north facing slopes in rocky, alpine terrain with a shallow or highly variable snowpack depth.

Moderate - Due to the number of field observations

SATURDAY NIGHT: Cloudy with alpine flurries; 3-5 mm / Light, northeasterly winds / Alpine low 0 C / Freezing level 2000 m.SUNDAY: Cloudy with alpine flurries; 3-5 mm. / Light, easterly winds / Alpine high 1 C / Freezing level 2000 m.MONDAY: Mix of sun and cloud / Moderate, southwesterly winds / Alpine high 2 C / Freezing level 2100 m.TUESDAY: Cloudy with alpine flurries; 3-5 mm. / Strong, southwesterly winds / Alpine high 1 C / Freezing level 2000 m.

Natural avalanche activity will taper off with the cloudy skies and cooling temperatures. Concern remains for human triggering persistent slab avalanches; especially on northerly aspects in the alpine.Thursdays reports show continued skier triggered loose wet avalanches reaching size 1.5 on sun-exposed aspects. Check out this video of our South Rockies Field Team HERE.On Wednesday, several avalanches that began as loose wet point releases, then triggered small slabs which entrained or gouged out additional mass, significantly increasing the size and destructive potential of the avalanche.

The prolonged warm spell has transitioned sun exposed slopes in the alpine and all aspects at treeline and below towards becoming isothermal (0 C throughout the snowpack). In these areas that have entered spring conditions, the avalanche hazard will fluctuate greatly depending on the strength of the overnight freeze and how quickly the snowpack is warmed up each day. Check out this guide to managing avalanche hazard during spring conditions HERE.In areas that remained more sheltered from the heat, like northerly aspects in the alpine, there may still be a dry snowpack with a well settled slab sitting on weak facets (sugary snow). Human triggering of persistent slabs on this layer may still be possible; especially in rocky alpine terrain with a shallow or highly variable depth snowpack.