Naturally triggered loose wet avalanches remain likely on Friday. Avoid sun exposed slopes during the heat of the day.
Weather Forecast
THURSDAY NIGHT: Clear skies / Light, southeasterly winds / Alpine low 6 C / Freezing level 3000 m.FRIDAY: Sunny / Light, westerly winds / Alpine high 6 C / Freezing level 2800 m.SATURDAY: Mix of sun and cloud / Light, northerly winds / Alpine high 0 C / Freezing level 2400 m.SUNDAY: Snow/rain; 5-10 mm. / Light, southeasterly winds / Alpine high -3 C / Freezing level 1700 m.
Avalanche Summary
Wednesday's reports show continued loose wet avalanches reaching size 2 on sun-exposed aspects. 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.Reports from Sunday and Monday showed a continuation of natural loose wet avalanche activity focused on sun exposed aspects, with some releases reaching size 2.5 as they gouged into the snowpack to entrain more mass. Several large persistent slab releases have also been noted failing on large alpine features and reaching size 2.5. Failure planes in these events seem to indicate faceted snow in the mid-snowpack. At least one northeast aspect was included in these reports, suggesting some increasing potential for shaded aspects.Natural avalanche activity is expected to continue until things cool off a bit.
Snowpack Summary
Upper snowpack: Getting warm and moist during the day, maybe forming weak crusts overnight that deteriorate during the day. On sunny aspects the upper snowpack has become increasingly isothermal (slushy and cohesionless) with successive days of warming. Mid-pack: The mid-snowpack consists of weak facets (sugary snow). Recent loose wet avalanches have been gouging into this faceted snow and entraining additional mass. Occasional slab fractures have also initiated above these facets.The lower snowpack has recently been reported to be strong in deep snowpack regions, but its strength is in doubt in shallow areas where the long, cold drought in February weakened the basal (bottom of the snowpack) layers. Some of the largest recent slab avalanches have initiated in shallow snowpack areas in the alpine.
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.
Wet Slabs
Wet Slab avalanches are the release of a cohesive layer of snow (a slab) that is generally moist or wet when the flow of liquid water weakens the bond between the slab and the surface below (snow or ground). They often occur during prolonged warming events and/or rain-on-snow events. Wet Slabs can be very unpredictable and destructive.