Avalanche Forecast
Issued: Dec 20th, 2013 8:31AM
The alpine rating is Wind Slabs and Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Fair - Timing, track, or intensity of incoming weather system is uncertain
Weather Forecast
Saturday: Mainly cloudy with a chance of flurries and sunny breaks. The freezing level could jump to 700 m and moderate gusty northwest winds continue. Sunday: Possible sunny breaks and flurries. The freezing level could climb to 1500 m in parts of the forecast area. The upper flow continues to be northwesterly. Monday: 5 to 10 cm of snow at upper elevations, freezing level to remain at valley bottom for most of the area.
Avalanche Summary
No avalanches have been reported in the last few days.
Snowpack Summary
It's been an exceptionally dry December so far. The total monthly precipitation in Nelson is 40 mm, and 30 mm of that fell in one storm at the beginning of the month. Hopefully the weather pattern changes soon!Recent light snowfall and strong westerly winds formed pockets of soft wind slab on lee slopes and scoured windward slopes in exposed terrain. Between 35 and 50cm below the surface you may find a weak layer of surface hoar on sheltered slopes or a melt-freeze crust on steep solar aspects. Most reports indicate this layer is "stubborn" to trigger, or there may not be a deep enough overlying slab to create a significant hazard. That said, I'd remain curious about this interface, especially as the snow load above gradually increases.In general, snowpack depths are below seasonal average and many slopes below treeline are reported to be below threshold for avalanche activity. Deeper snow is likely in the northern part of the region.
Problems
Wind Slabs
Aspects: North, North East, East, South East, South.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 21st, 2013 2:00PM