YESTERDAY:
Sunrise Friday was at 07:28 Hrs. At 2240 m it was -20 with a 30-40 KPH East wind. -33 wind chill.2240 meters -11, Winds were 30-45 KPH E--Horstman Hut
1860 meters -16, Winds were 5-10 KPH NNE --Rendezvous
1570 meters -16, 1 cm in 12 Hrs, 1 cm in 24 Hrs, Base 175 cm--Catskinner
FORECAST:
Overcast with periods of light snow for today in a Westerly flow aloft. The FL will remain well below surface with slightly warmer temps. Light snow should diminish to flurries by the afternoon. Overcast skies for tonight with another weak impulse of moisture and unsettled conditions for Sunday. Likely see some brief breaks around noon on Valentines Day. Another weak impulse of moisture arrives early Monday morning with periods of light snow, temperatures back to normal values for this time of the year. Spotty snow for most of next week with a proper front arriving Saturday and Sunday. More on that as we get closer. Guesstimates: 1-5 cm by Sunday am, 1-5 cm by Monday am, 1-3 cm by Tuesday am, trace to 1 cm by Wednesday am.
AVALANCHE ACTIVITY:
Blackcomb patrol responding to an avalanche in the Poop Chutes, 1 fatality. Article below.AVALANCHE SUMMARY FOR SEA TO SKY AREA:
Avalanche Summary
We have preliminary information about a large (size 3) avalanche occurring in the vicinity of Blackcomb Mountain on Friday. We will update this summary once we have more details.
A bout of strong northerly winds on Thursday caused conditions in the region to change rapidly, with new and touchy wind slabs forming in many leeward terrain features. Numerous natural releases from size 1 to size 2 were observed in the Whistler area above about 1900 metres. We are awaiting further detail about a skier-triggered avalanche that occurred in the Mamquam Glacier area on Thursday.
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
Ongoing elevated winds from the east and northeast have been redistributing loose snow into reactive new wind slabs in the lee of exposed terrain features at higher elevations.
The snow surface otherwise is composed of up to 15 cm of low density snow in shaded, sheltered areas (now likely a bit more scarce), along with more widespread wind-affected surfaces, including older wind slabs that have been gradually losing cohesion and reactivity under prolonged cold temperatures. On solar aspects, a thin recent sun crust may be found on or right near the surface or beneath recently wind transported snow, potentially contributing to the reactivity of new slabs on sun-exposed aspects.
Below these variable 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 suspect, we have no recent reports of avalanches failing at this interface within the region. Details of the failure planes involved in two recent avalanches are still pending.
A crust from early December, currently considered dormant, may be found around 200+ cm deep in the snowpack.
INFORMATION & OBSERVATIONS:
First light East side of Mount Currie.Always a good idea to keep your skills tuned.
RECENT MIN REPORTS FROM SEA TO SKY:
Vantage Ridge : Feb 11, 2021
Chief Pascal: Feb 11, 2021
Decker Main Avalanche: Feb 12, 2021
Big sastrugi, big wind slabs: Feb 12, 2021
Gin Peak N Bowl: Feb 12, 2021
Gin Peak wind slabs: Feb 12, 2021
Rainbow SE Route-Wind Slab Point Release: Feb 12, 2021
Birkenhead: Feb 12, 2021
VIDEOS:
Whitewater Avalanche Report : Feb 12, 2021
Powder Picker Jan 12, 2021: David Jones
ARTICLES:
Skier killed others injured in avalanches above Blackcomb Glacier: February 12, 2021
An avalanche has killed a ski tourer in Switzerland: Feb 11, 2021
Man killed in East Vail avalanche was standing in a spot "he felt safe" when he was buried: Colorado
Natural avalanches in the Sherwins: California
Backcountry on alert amid increasing avalanche danger: Utah
Avalanche Safety Guidelines, knowledge could save lives during snow season: Utah
'Heroic" avalanche survivors dug out strangers as time worked against them: Utah
Surge in women becoming ski patrollers, once all men (not on Blackcomb): NYT
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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