Regions
South Coast Inland.
A natural avalanche cycle is expected on Sunday with rain set to batter the snowpack. Conditions will be especially dangerous where rain falls on dry snow. This will certainly be the case at high elevations in the south of the region.
Weather Forecast
Sunday: Approximately 20mm of rain in the south of the region with 10-15 cm of new snow at alpine elevations in the north. Rain below about 1700 metres. Strong south winds. Freezing level ranging from 2000-2200 metres with alpine temperatures from +3 in the south to around 0 in the north.Monday: Mainly cloudy with isolated flurries and a trace of new snow in the north of the region. A possible 5 cm of new snow in the south. LIght to moderate southwest winds. Freezing level to around 1200 metres with alpine temperatures of -5 in the north of the region and -3 in the south.Tuesday: Cloudy with scattered flurries and approximately 5 cm of new snow at higher elevations. Rain below about 1200 metres. Strong southwest winds. Freezing level to about 1600 metres with alpine temperatures from about -1 in the south of the region to -3 in the north.
Avalanche Summary
No new avalanches have been reported, however new storm slabs developed at upper elevations in the south of the region over last week's stormy weather. Please post your observations to the Mountain Information Network. (MIN)
Snowpack Summary
Up to 10 cm of new snow lies on the surface above about 1300 metres in the north of the region, with up to 35 cm in the south. Recent southerly winds have redistributed the new snow into wind slabs in lee terrain. Areas that received more snow may still be presenting a more generalized storm slab problem on all aspects. Below the new snow, last week's warm and wet weather saturated the snowpack with rain. This will have refrozen into a strong capping crust below the new snow at higher elevations but may remain moist below treeline and into the valley bottom. Below this variable crust interface the heavy rain eroded snowpack depths significantly, leaving behind a rain-soaked and relatively uniform 90 cm at treeline elevations throughout the region.
Problems
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
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.