April 12, 2015

    An avalanche has killed a man near Big Sky Montana, story in article section.              Net Pic

    08:00 Hours Saturday morning.

    Early Saturday April 11, 2015--Cloudy in the valley.

    Some great breaks in the cloud on Saturday morning.

    Shack Booter on Blackcomb.

    Pow turns amongst the cornice debris, Blackcomb Bowl.

    Girls were sending it Saturday morning.

    Snowing in the valley Saturday afternoon.

    Just before sunset Saturday evening. Snowing lightly.


Weather Observations for April 12, 2015; taken at 06:00 Hours.

2240 meters    -12, Winds were 20-30 KPH from the S
2180 meters    -10, Winds were 25-40 KPH from the SSW
1860 meters    -10, Winds were 15-20 KPH from the E
1835 meters      -8, Winds were 10-30 KPH from the SSW
1650 meters      -7, 4 cm of new snow, 5 cm in 24 hours,  Base 194 cm
1550 meters      -7, 3 cm of new snow,  Base 148 cm, Relative Humidity 85%. 

  660 meters     -1, Valley Temp, Max Temp Yesterday was +7.0, 1.6 mm recorded there on Saturday.

   As of 07:00 Hours this am we have broken cloud and unlimited visibility.

Yesterday, avalanche control on WB produced size 1-2 soft slab avalanches with explosives and ski cutting. Several small size 1 Sa ( Skier accidental) were reported in the backcountry.


For the forecast, an upper trough in a moderate Westerly flow brought cool showery weather last night with the freezing level dropping to the surface. A weak upper ridge and surface high will bring unsettled conditions (mostly cloudy) for this morning with cloudier skies this afternoon and some snow showers possible with the remaining instability in the cool air mass.  The FL will rise to 1200 meters than drop back down to 800 meters tonight.  A cold front emanating from the deep low to the Northwest will bring light to heavy precipitation to the area Monday into Tuesday morning. We can expect strong winds with the arrival of the front. A weak surface trough and high pressure to our South will bring some showers to the area on Tuesday with unsettled conditions into Wednesday. The Fl will drop to the surface in the evenings and rise to about 1200 meters during the day. Medium range models are in disagreement to what will happen beyond Wednesday, so more on that as we get closer. Likely a typical showery spring pattern with warmer temperatures than we have been experiencing.  Guesstimates: 3-5 cm by Monday morning, 15-18 cm by Tuesday morning, Trace to 2 cm by Wednesday morning, trace to 2 cm by Thursday morning.

    Breaks this morning with cloud this afternoon.

    Looks like a nice morning.

    Flow into Tuesday.

    Cold front arriving tomorrow.

    Cloud Tuesday morning with unsettled conditions in the afternoon.



ARTICLES:

Bozeman man dies in avalanche North of Big Sky: Montana

Spring Dangers: Pistehors.com

Heats role in the Madden-Julian Oscillation: Science Daily

29 avalanche fatalities in the Swiss Alps so far this year: Geneva

Italian mountain Guide killed in an avalanche on April 5, 2015: Valley of Silence

Report outlines compelling economic case to protect B.C. snow sport resorts: Whistler

    Satellite image Saturday afternoon, enough convective activity to produce some snow last night.

    Big picture yesterday afternoon.

    Convective cloud development Saturday morning.

    Line up at the Whistler Gondola

    Fairly large lift lines Saturday morning. GE line up got bigger.

    Pow frenzy yesterday morning.

    Nice to make some pow turns yesterday morning.

    Creekside download yesterday at 14:45.                                                                 Jeff Yarnold Pic

    Convective clouds produced graupel yesterday.                                         Bridgett McClarty Pic

    Nice to see fresh snow on the snow guns.