Watch for clues of changing conditions as there is potential for fresh wind slab formation on alpine features late Friday.
Confidence
Fair - Forecast snowfall amounts are uncertain on Friday
Weather Forecast
FRIDAY: Freezing level holding at 2000m. Moderate SW winds at treeline, strong SW winds at ridge-top. Overcast. No significant precipitation expected during the day. On Friday night 2 to 6mm of precipitation is possible, less than 10cm of total snow expected.SATURDAY: Freezing level hovering around 1500m. 2 to 4mm precipitation possible, 2 to 10cm of snow expected. Moderate SW winds at treeline, moderate to strong SW winds at ridge-top.SUNDAY: Freezing level starting at 1000m, rising to 1500m. Moderate W/SW winds at all elevations. Overcast. No significant precipitation expected.
Avalanche Summary
On Wednesday loose wet avalanches averaged size 1, with a size 2.5 being reported from steep rocky terrain. Observations from Sunday, Monday and Tuesday were limited to power sluffing from steep high elevation terrain and small loose wet activity.
Snowpack Summary
The current surface consists of surface facets and surface hoar. Below this is the 10 to 45cm of snow that fell last weekend. This snow remains dry on high elevation polar aspects but has turned moist on east and west facing aspects and south facing features are moving into the spring corn cycle. Just below this snow you'll the supportive late-March crust that is thought to exist up to around 2100m. Moist snow underneath the late-March crust is ubiquitous in most of the region.Two significant persistent weak layers composed of crust and facets exist in the snowpack. Although they appear to have gone dormant for the time being, we will continue to monitor them closely. Mid-March is down 40 to 80cm below the surface and Mid-February is down 80 to 140cm. Observations indicate that there is significant faceting occurring between the two crusts. While an avalanche failing at either of these interfaces is unlikely, it may still be possible on steep unsupported alpine features.
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.
Cornices
Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.