Northwest Inland

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

Moderate - Due to the number of field observations

SATURDAY NIGHT: Partly cloudy / Light, southeasterly winds / Alpine low -3 C / Freezing level 700 m.SUNDAY: Mostly sunny / Light, easterly winds / Alpine high -1 C / Freezing level 1500 m.MONDAY: Mostly sunny / Light, easterly winds / Alpine high -2 C / Freezing level 1400 m.TUESDAY: Cloudy / Light, southwesterly winds / Alpine high -2 C / Freezing level 1400 m.

Natural avalanche activity has tapered off with the cloudy skies and cooling temperatures. Concern remains for human triggering persistent slab avalanches on a layer of facets that are down 30-50 cm; especially in steep, rocky alpine terrain with a shallow or highly variable snowpack depth.

At upper elevations, 30-50 cm of well settled snow overlies weak facets (sugary snow) that were around March. 10th. which is currently the primary layer of concern for human triggering persistent slab avalanches.Lower down in the snowpack, the base is composed of weak facets. Large avalanches initiating on these facets are most likely in rocky, alpine terrain where there is a shallow or highly variable snowpack depth. They would likely require a large trigger such as a cornice fall, snowmobile, or a group of people standing in the same spot.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.