18 Mar 2013

Skier released slab on Sign Line Pillow on Blackcomb Mountain. Patrol released slab while doing control work.  A similar release occurred here March 2, 2013 while doing avalanche control. 1F+/P stiff slab West Aspect on 13-03-11 mfc. Likely facets on the crust.



In the corridor there were Size 1-3 soft and stiff slabs reported yesterday.



At 2240 meters the temperature was -11, winds were 25-45 KPH from the E. At 1650 meters the temperature was -7, 5 cm of new snow was recorded overnight, expect another 1-2 cm. In the valley it was -1. Observations taken at 06:00 Hrs.

For the forecast we can expect unsettled conditions for today as the North West Flow aloft gives way to  a weak high pressure system giving us drier conditions. Light snow this morning tapering off by this afternoon.  A warm front will arrive on Tuesday afternoon bringing moderate to heavy precipitation and strong winds, the strong westerly flow aloft will continue into Thursday when a broad trough brings unsettled conditions into  Friday. The models are conflicting on a possible weak ridge for Saturday, only time will tell!! Hard to guesstimate convective flurry activity, certainly off on the numbers last night. For today 0-2 cm, Tuesday 0-1, Wednesday 15-25, Thursday 15-20, Friday 3-5



For the local updated avalanche advisory: Blackcomb Snow Safety



Colorado System for investigating ski accidents raises concerns: Denver Post


Thanks to Jeff Van Driel for sending the link to this video, skier getting caught on a slab avalanche :Mt. Owen , Colorado

Garabaldi Provincial Park: Trail Reports

Avalanche at Aspen's Snowmass Ski Area: March 17, 2013

Colorado: No El Nino, No La Nina - What is driving the weather? : La Nada


Some intel from the Duffy Zone:

Hi Wayne,

We were looking forward to some whiteout travel on the NE glacier on Cayoosh. We had to cross a bench connected to some SE aspects above. As we approached the bench on similar terrain to the exposure, at 1950m, I got a CTM(11) SC down 60cm on 2mm facets on a 4cm crust. Poking out a little further got a significant settlement on this layer. Just adjacent to this location revealed this layer to be down a meter and resulted in an ECTP(13) SC as well as a few more settlements. Ski pen was 20cm and boot pen 50cm, - 5.0, obscured skies and light NW winds.  With few options we bailed and found good quality skiing to 1800 meters and dust on crust below. Sorry, no photos.
Cheers
Jeff Van Driel

Future snow scientists measuring the convective flurry activity yesterday. Not quite a centimetre at 11:00 Hrs.

Depending where you were on the mountain yesterday, it was snowing moderately at times.

There were lots of locations that were skiing well with knee deep powder. The higher the deeper.

There were some breaks during the day with good visibility.

What it looked like yesterday afternoon.

Close up of our zone.