YESTERDAY:
Thursday sunrise was at 07:29 Hrs. -19 with a 10-30 KPH East wind.2240 meters -19, Winds were 20-40 KPH ENE-Horstman Hut
1860 meters -23, Winds were 5-10 KPH SE --Rendezvous
1570 meters -23, Trace in 12 Hrs, trace in 24 Hrs, Base 175 cm--Catskinner
FORECAST:
Unsettled weather for today with a mix of sun and cloud in a Northerly flow aloft. The Arctic front remains strong and looks to deflect any incoming lows to our South. More sun than cloud this am but most of the moisture will stay along Vancouver Islands coast. Saturday will hopefully bring some snow as the low moves down the coast. Expecting periods of light snowfall early Saturday morning into Saturday afternoon. A break Saturday night with overcast skies and moderating temperatures. Periods of light snow again by Sunday afternoon into Monday. Arctic front loses ground and we should see some decent snowfall by Monday.? Unsettled by Tuesday with seasonable weather. Guesstimates: 2-6 cm by Saturday am, 2-5 cm by Sunday am, 2-6 cm by Monday am. Could get a little less or a little more depending on how the Arctic front reacts to the incoming low.

AVALANCHE ACTIVITY:
Sa Sz 1.5 Stiff Slab NW aspect Decker Main on Thursday. Skier sustained knee injury.Two backcountry skiers had to be rescued by military helicopter near Spire Peak. Article below.
AVALANCHE SUMMARY FOR SEA TO SKY AREA:
Avalanche Summary
With cold temperatures gradually robbing the upper snowpack of cohesion, observations from the past few days show a trend away from wind slab releases and toward small loose dry avalanches triggering in steep start zones with skier traffic. That said, a few more small wind slabs were still able to be triggered with ski cutting in the Whistler area on Tuesday.
Notably, a size 3 (very large) persistent slab was remotely triggered (from a distance) by a group of skiers in the McGillivray Pass area (northern South Coast Inland region) on Monday. This occurred on a southwest aspect at 2400 metres. It was described as a hard wind slab formed over the facet layer from late January detailed in our snowpack discussion.
Snowpack Summary
Up to 15 cm of low density snow can be found on the surface in shaded, sheltered areas. In more wind exposed areas this is replaced with a mix of wind-affected surfaces, including wind slabs that are gradually losing cohesion and reactivity under prolonged cold temperatures. A thin recent sun crust may be found right near the surface on solar aspects.
Below this mixed bag of surface conditions, 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 a bit 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:
Wednesday turns. Lots of spindrift yesterday.RECENT MIN REPORTS FROM SEA TO SKY:
Ledge Basin Wind Slabs: Feb 11, 2021
VIDEOS:
Powder Picker Feb 11, 2021: David Jones
ARTICLES:
Two men rescued by military helicopter from Mamquam Lake: Squamish
Two men rescued after avalanche?? near Squamish: Spire Peak
Two injured in an avalanche on Mt Earnslaw near Queenstown: New Zealand
Managing Moderate: Avalanche Canada
Thinking in Risk: Powder Cloud
Lawsuit filed against Alpine Meadows for fatal 2020 avalanche: California
Winter sport season also avalanche season: Be Prepared
Fatalities up as skiers/boarders choose backcountry over resorts & restrictions: Colorado
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