YESTERDAY:
Busy Wednesday morning.2240 meters -8, Winds were 15-20 KPH SE--Horstman Hut
1860 meters -9, Winds were 0-5 KPH S--Rendezvous
1570 meters -6, 0 cm in 12 Hrs, trace in 24 Hrs, Base 169 cm--Catskinner
FORECAST:
A weak short lived high will bring unsettled weather for today in a Westerly flow aloft. Cloudy this am with sunny breaks later in the am, increased cloud cover near the end of the day with a weak short wave trough pushing through tonite into early Friday in a South West flow aloft and strong winds. The FL may rise to above 2000 meters today as the system draws warm air from the south. Hoping it hovers around 1600 meters, dropping to 1000 meters tonight. Unsettled weather Friday with weak ridging, bringing a mix of sun and cloud. Saturday is looking cloudy and gray with cooler temperatures and another weak front arriving Saturday night into Sunday. Weather will dry out next week! Guesstimates: 8-12 cm by Friday morning, 0 cm by Saturday am, 8-12 cm by Sunday am.
AVALANCHE ACTIVITY:




Avalanche Summary
On Wednesday, there were reports of numerous natural slab avalanches up to size 3 above 2000 m from N-NW aspects. Most of these were triggered within the storm slab and stepped down to deeper persistent weak layers. I suspect more observations will be made with good visibility on Wednesday and Thursday.
Last Saturday, a large (size 3) avalanche was remotely triggered by skiers on Cowboy Ridge near Whistler. The avalanche occurred on a north to northwest aspect at around 1900 m. The crown ranged reached up to 200 cm and was approximately 200 m wide. Check out this MIN for photos and more information. A similar avalanche was remotely triggered by skiers on a nearby westerly slope a few days before; check out this MIN for more info and photos.
The weak layers described in the Snowpack Summary may continue to lurk post-storm. If triggered, the consequence of being caught would be high.
Snowpack Summary
Up to 50 cm of recent storm snow blanketed the region and buried another surface hoar layer in wind-sheltered terrain. The new snow combined with strong to extreme wind by Wednesday morning has formed new and reactive storm and wind slabs. Below 1900 m the upper snowpack may see a firm melt-freeze crust.
The snowpack is currently quite complex. Deeper in the snowpack numerous layers of surface hoar may be found down 100 to 200 cm. This is the depth of the greatest concern, where surface hoar or sugary faceted grains may sit above a hard melt-freeze crust from early December. Last weekend, several large natural and human-triggered avalanches on this layer occurred, with the hot spots being around the Whistler backcountry.
Near the base of the snowpack, there may be faceted grains above a crust from early-November, which was identified as the failure layer in recent sporadic large avalanche releases.
LOCAL AVALANCHE CANADA MIN REPORTS:
Rohr Lake Area: Jan 13, 2021
Cowboy Ridge Na Sz 2: Jan 13, 2021
Rewind: Jan 13, 2021
Joffre Shoulder: Jan 13, 2021
VIDEOS:
Huge Avalanche : Nepal
Travelling through terrain & decision making: CBAC
ARTICLES:
Avalanche reported at Sun Peaks' slackcountry over the weekend: Sun Peak News
Latest backcountry advisory for the Whistler Area: Avalanche Canada
New Avy Savvy online tool helps novice winter backcountry users: Avalanche Canada
Weak snow layers lead to avalanches: Colorado
Highly trigger-sensitive snowpack: Austria
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