Avalanche Forecast

Moderate -

A significant warm-up is happening and will continue through the week with above freezing level to the summits. Unfortunately, very little overnight re-freeze is expected during the warm spell.SUNDAY NIGHT: Clouds disappearing, warming temperatures overnight with above freezing temperatures at treeline in the morning.MONDAY: Clear and dry. Freezing level around 3000 m with no overnight freeze. Light south wind.TUESDAY: similar to Monday.WEDNESDAY: similar to Monday and Tuesday but possibly slightly lower freezing level, say 2500 m.

Fewer avalanche activity reports on Saturday and Sunday with smallish loose wet, loose dry, and windslabs.For me the most important avalanche data over the past few days were SEVERAL REMOTELY TRIGGERED AVALANCHES (some of these reports were from areas outside the forecast region but are relevant to the region's conditions). Skiers are whumpfing the snowpack, often when they group up, with avalanches releasing at a distance (sometimes on the slope above). Reports include this happening on previously skied terrain, include releasing several avalanches from a single whumpf, and avalanches releasing and running over normal "ski lines".

Between 50 and 100 cm of "settled" snow since the drought ended March 10. At lower elevations the most recent precipitation came as rain. The recent snow is settling into a slab with the warm temperatures: however, it's covering a wide variety of old snow surfaces: crusts on solar aspects, facets up high, and surface hoar in sheltered locations. Not much further below this storm snow interface is a second weak layer buried on February 19 made up of weak facets and surface hoar crystals. Recent avalanche activity was more or less equally split between these two layers. The lower snowpack is generally strong.The Avalanche Activity section below highlights remotely triggered avalanches: the recent storm snow is settling into a cohesive slab, the old cold weak layers remain. For slightly complex reasons (snowpack creep, strain rates, viscous coupling, and similar geeky snow science stuff) warm temperatures are keeping the snow stability balance near a tipping point.