YESTERDAY:
Sunrise was at 08:11 Hrs Wednesday. -4 with a 20-30 KPH ESE wind. -2 in the valley.2240 meters -6, Winds were 10-15 KPH SE--Horstman Hut
1860 meters -4, Winds were 0-5 KPH SE --Rendezvous
FORECAST:
Unsettled early this am with a ridge building in a Northerly flow aloft. Should see the sun later this morning, clouds move in this afternoon before the next wet, warm, windy front arrives Friday morning. For today we can expect the FL to rise to around 1400 m. The strong front tomorrow will be drawing moisture from the Pineapple States so the FL might exceed 1800 meters, hoping that it stays a bit lower. Some models are suggesting 1500 meters, time will tell. Friday's storm will be in a South Westerly flow aloft with winds 80-100 KPH and possibly stronger at 2240 meters. Light to heavy precip is expected Friday through Saturday. The brunt of the moisture will likely fall Saturday night. The FL is forecasted to drop back down to surface by Sunday. Drying trend on Sunday with a chance of some sunny breaks, but short lived as another strong front arrives for Monday into Tuesday. Guesstimates: 8-12 cm by Friday am, 30-40 cm above 1600 meters by Saturday am, 40-60 cm above 1600 meters by Sunday am, 5-10 cm by Monday am.
GOES IR image this am.
AVALANCHE ACTIVITY:
An avalanche has killed a ski tourer from Belgium in Switzerland. Article below. Net Pic
From the Sea to Sky Advisory:
Avalanche Summary
There were numerous explosives triggered storm slab avalanches reported on Wednesday, mostly size 1, with one size 2 and one size 3.
There was a fatal avalanche in the South Coast Inland region (near the Sea to Sky boundary) north of Pemberton in the Railroad Pass area on Monday that resulted in two fatalities. It was reported to be a size 2 persistent slab avalanche on a west aspect, around 1650 m. The RCMP press release can be viewed here, and the Avalanche Canada report can be found here.
A size 2.5 avalanche was triggered on Monday by a skier on Rainbow Mountain, which resulted in a full burial and, thankfully, a successful rescue. The avalanche failed on a 60 cm deep crust and facet layer on a northeast aspect around 1800 m.
A natural size 3 persistent slab avalanche was reported on Mount MacBeth on Monday, check out this MIN report for details of this observation.
These avalanches highlight the ongoing potential to trigger persistent weak layers in the snowpack.
There were several other human triggered wind slab avalanches up to size 2 reported on Monday as well.
Snowpack Summary
There has been between 40-70 cm of recent snow in the region with strong southwest winds. The fresh snow has likely been redistributed by the wind, forming storm slabs in lee terrain features.
The snowpack is currently complex, and two concerning weak layers may be present in the snowpack:
- The shallower layer, around 60 to 100 cm deep, includes feathery surface hoar crystals. This layer may be found in sheltered terrain features at treeline and lower alpine elevations, but has been reported as spotty across the region.
- The more widespread weak layer includes sugary faceted grains that sit on top of a hard melt-freeze crust. This layer ranges in depth from 20 cm to 120 cm due to the wind scouring and loading the snow in different terrain features over the past two weeks. The layer has been reported as being widespread up to around 2000 to 2200 m.





LOCAL AVALANCHE CANADA MIN REPORTS:
Mount Chief Pascal Trees: Dec 29, 2020
Cayoosh-Laziest Boy Ridge Top: Dec 29, 2020
Sentinel Ridge: Dec 30, 2020
Chief Pascal: Dec 30, 2020
Steep Creek: Dec 30, 2020
Hanging Lake Area: Dec 30, 2020
Small Slide: Dec 30, 2020
VIDEOS:
I got hit by an avalanche: Norway
Powder Picker Dec 30, 2020: David Jones
ARTICLES:
Belgian ski tourer dies in an avalanche in Lower Valais: Switzerland
Weak snowpack layers taking lives: Powder Canada
Explosive charges protect backcountry Skiers: Scientific American
Avalanche danger runs highest in years as state records one of its busiest months: Colorado
Avalanches triggered by humans 'almost certain' for North Shore Mountains: NSSR
Avalanche threat rises on Vancouver Island: Courtenay
Several avalanches involving persons-No Injuries: Austria
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