YESTERDAY:
Sunrise was at 07:22 Hrs on Tuesday. -7 at 1860 m with 0-5 KPH S breeze.2240 meters -12, Winds were 40-65 KPH NNE--Horstman Hut
1860 meters -9, Winds were 30-40 KPH N --Rendezvous
1570 meters -7, 1 cm in 12 Hrs, 1 cm in 24 Hrs, Base 179 cm--Catskinner
FORECAST:
Brief ridging for this am in a Northerly flow aloft. The FL may rise to around 800 meters today dropping down to surface by tonight. Sunny skies will give way to some cloud later in the afternoon. Front arrives Thursday morning with periods of light snow. Another weak front arrives Friday morning with periods of light snow. More light snow for Saturday before a potent West Coast storm arrives for Sunday with wet warm windy weather. As of now it looks like the FL will stay below 1500 meters for Sundays event. Guesstimates: trace-1 cm by Thursday morning, 5-10 cm by Friday am, 5-10 cm by Saturday am, 10-15 cm by Sunday am, 30-50 cm by Monday am. Models are not in agreement with this much snow, time will tell.
AVALANCHE ACTIVITY:
Some loose dry activity yesterday.Avalanche Summary
Recent outflow winds created a widespread and reactive windslab problem that continued to produce avalanches on Monday. A size 2 persistent avalanche was triggered by a skier on the west side of Blackcomb Peak, the crown ranged from 5-90 cm and failed on facets. A size 1.5 windslab was remote triggered on the northwest face of Oboe. Additionally, numerous dry-loose avalanches were observed up to size 2, many running far and entraining large amounts of snow. Wet-loose avalanches failed naturally and were reactive to skiers Monday afternoon.
Sunday was a much quieter day for avalanche activity. Avalanche control work produced very small avalanches with the exception being a single size 2.
A fatal avalanche occurred in the region on Saturday in the Brandywine valley. The person caught was carried several hundred metres over steep, rugged terrain and through treed slopes below. The avalanche is described as a size 1 (small) wind slab on a southwest aspect at 1700 metres. The incident report can be seen here.
On Friday, a large (size 2.5), fatal avalanche was triggered by skiers at 2200 metres on a west-facing slope on Phalanx Mountain. The avalanche is described as a wind slab that formed to the lee of recent strong east winds. Two people out of a group of three were involved in the avalanche and one person was killed. The incident report can be seen here. A second, smaller (size 1.5) wind slab was triggered by skiers on a nearby slope, again causing injury to the person involved.
A bout of strong northerly winds on Thursday caused conditions in the region to change rapidly, with new and touchy wind slabs forming in unusual places. Numerous natural releases from size 1 to size 2 were observed in the Whistler area above about 1900 metres on and since Thursday.
It is important to note wind has not affected elevation bands uniformly across the region, with heavy wind effect and slab formation noted even below treeline in some areas. This is a critical piece of information as new snow obscures existing wind slab formations.
Two more skiers were involved in an avalanche in the Supercouloir feature of Mamquam Mountain on Thursday. This avalanche was a natural wind slab release and again resulted in serious injuries and an urgent evacuation by helicopter.
Snowpack Summary
10-30 cm low density snow overlies a variety of wind affected surfaces and facets in the alpine and into treeline. Isolated windslabs remain reactive from recent outflow winds. New, thin windslabs have formed in lee terrain. A thin melt-freeze crust has developed on solar aspects.
Below the evolving surface, 50-100 cm of settled storm snow sits on a persistent weak layer from late January that consists of facets at upper elevations, surface hoar in sheltered areas, a melt-freeze crust below 1900 m, and a sun crust on south-facing slopes. There could be more than 100 cm on this layer in wind loaded areas. Although this structure is suspect, we have no recent reports of avalanches failing at this interface within the region.
A crust from early December, currently considered dormant, may be found around 200+ cm deep in the snowpack.
INFORMATION & OBSERVATIONS:
1-2 cm brittle crust on solar aspects. There is a temperature crust on other aspects. Buried 2-5 cm.FROM SEA TO SKY MIN REPORTS:
Oboe, Singing Pass: Feb 16, 2021
VIDEOS:
Powder Picker Feb 16, 2021: David Jones
ARTICLES:
Avalanche Canada spokesman describes Whistler -Area avalanche conditions as "Tricky": Ilya Storm
Snowboarder killed in Whistler-Area avalanche was trying to get to safety: CBC News
Squamish Climber/Snowboarder dies in Avalanche: Gripped
B.C. man survives avalanche by triggering his airbag: Kootneys
Man sues Tahoe Ski Area after avalanche injuring him, kills friend: California
68 Avalanche Fatalities in Europe so far in the 2020/2021 season: EAWS
Avalanche hits Grieg salmon farm: Norway
Satellite images show trail of destruction after Uttarakhand avalanche: Northern India
NY officials warn of avalanche danger: Adirondack Mountains
Roads closed due to "Extreme" avalanche risk: Utah
Mini avalanche traps car in Big Cottonwood Canyon: Utah
Skiers, snowboarders trigger multiple avalanches in Tahoe: California
Skier found dead in a tree well at Bridger Bowl: Montana
Submit your best avalanche photo for a pair of Goggles Feb 1-28, 2021. Sea to Sky Area.
Thanks to Volkl Canada for sponsoring.
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