26 Apr 2012

Visibility has been an issue for the past few days. Hopefully the weather will change today!!

At 2280 meters the temperature was -1.5 as of 06:00, winds were 20-40 KPH from the SSE.
At 1550 meters the temperature was 0, 100 % relative humidity and the barometer is on a slight downward trend. In the valley it is +6. 2 cm recorded at 1550, but 18.5 mil of precipitation fell since yesterday. Around 10 cm of new in the alpine. Wet size 1's at treeline and possibly wet size 2's in the alpine but visibility has been poor.


Today Jamie Selda and I skied from Blackcomb to just above Naden Pass to drop off some groceries. The alpine lifts on Blackcomb were closed due to avalanche hazard brought on my warm temperatures. (Whistler Mountain is now closed for the season) So we started skinning from the bottom of the 7th Heaven lift, and at tree line the snow was isothermal, deeper then I could easily feel with my hand. Above 1900m there was a thin crust that held the upper pack together well, except on sunlit aspects where I could ski cut small sluffs in steep terrain. This crust held through the day. High clouds and a cooler temps made for idea fast traverse conditions. Recent warm conditions have caused many avalanches off many sunlit features. It started snowing with a strong southerly wind at 6pm. By 8pm, as we left the alpine, there was about 5cm of new snow accumulated on the old surface. Precip was rain below 1700m.     
Dave Sarkany SG From April 25, 2012 ACMG Blog


For the latest Avalanche Advisory click here: Avalanche Advisory

Still no body recoveries from Kashmir Avalanche: Still Searching

Snow Pack properties of unstable wet snow slopes: Swiss Research


A wet snow avalanche


If the weather is too warm for too long the weakening of the snow bonds will occur to greater depths. In addition melt water may lubricate buried layers and interfaces which can serve as failure plains. Rain and/or warm winds can also contribute to this process. Crown lines of resulting slides may be quite deep and even go to the ground. These slides are generally unsurvivable. Typically the weather leading up to such an avalanche cycle will be very warm for an extended time (at least a couple days) without any refreezing of the snow pack overnight. Be wary if such a warm spell occurs. These conditions usually lead to numerous large slides, not isolated events. Word generally gets around that such a cycle is underway - check the avalanche advisories.