December 20, 2020

     YESTERDAY:

     Trees at 1000 meters are looking very white.

      Fissile was disappearing as the front moved in from the South.

      Nice turns to be had on the new surface.

      Saturday December 19, 2020. 14:00 Hrs. 5 with a 15-30 KPH ESE wind. +2 in the valley.

      Satellite image from same timeframe.

     Big picture Saturday afternoon.

Weather Observations for December 20, 2020 taken at 06:00 Hours.

2240 meters      -6, Winds were 60-90 KPH W--Horstman Hut

2180 meters      -6, Winds were 60-80 KPH SSW--Whistler Peak
1860 meters      -5, Winds were 20-40 KPH S --Rendezvous 

1835 meters      -3, Winds were 30-60 KPH SSW--Round House

1650 meters      -2, 19 cm in 12 Hrs, 21 cm in 24 Hrs, Base 146 cm --Pig Alley
1560 meters      -2, 12 cm in 12 Hrs, 13 cm in 24 Hrs, Base   92 cm--Catskinner

  660 meters     +2, Valley Temp, Max temp Yesterday was +2.5 7.1 mm of precip yesterday.

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

FORECAST:

The weakening front will bring unsettled weather for today in a Westerly flow aloft. Some lingering cloud with a slight chance of some flurries this am but looking like a stellar powder day.. The FL will hover in the 1000 meter range and slowly drop down to surface by tonight. A low pressure system will skirt the Whistler area tomorrow with light-moderate precip, moderate winds and cooler temperatures. The brunt of the energy may go South of our zone so difficult to guesstimate. Ridge of high pressure pushes in for Tuesday in to Thursday. Looking like snow for Christmas Day. Guesstimates: Trace to 1 cm by  Monday am, 10-20 cm by Tuesday am, 0 cm from Tuesday-Thursday.

      GOES IR image from this am.

      Weak upper trough for today with a drying trend this afternoon.

        Low will bring some precip for Sunday with cooler temperatures.

      High pressure builds for Tuesday.

     AVALANCHE ACTIVITY:

      A sledder has died in an avalanche in Wyoming. Report below.                         Robert Kincaid Pic

      AC on Blackcomb produced Sz 1-2 Xe, Xh, Sa. Some avalanches sliding on Dec 9 Mfcr.

      Lakeside Bowl.

     AC on Whistler produced Sz 1-2 with Xe and Xc. Some results on the Dec 9 MFcr.

     Variable depths of wind deposited snow on the Dec 9 MFcr. 10-80 cm.

From Sea to Sky Avalanche Advisory:

On Saturday, a naturally-triggered wind slab avalanche was observed on a southeast aspect in the north of the region. Other observations were limited due to poor visibility.

On Friday, a few storm slab avalanches were observed out of steep terrain and small wind slabs were triggered by riders on northerly aspects.

Slabs could be triggered by riders on Sunday from within the most recent storm snow, older storm snow, or on the weak layers described in the snowpack summary.

      INFORMATION & OBSERVATIONS:

     Nice soft snow in the 7th Heaven Trees.

      A very brief glimpse at the sun Saturday am.

      Purple Hayes

      Wet enough in the valley for a snowman.

LOCAL AVALANCHE CANADA MIN REPORTS:

Brandywine: Dec 19, 2020

Chief Pascal: Dec 19, 2020

Bullet Proof Crust-South Coast: Dec 19, 2020

Alpen-South Coast: Dec 19, 2020

VIDEOS:

Powder Picker Dec 19, 2020: David Jones

ARTICLES:

A sledder has died in an avalanche near Sheep Pass: Wyoming

Avalanche claims the life of Crested Butte Legend: Gunnison Country Times

Snowpack is pretty complicated on the South Coast: North Shore

Colorado ski resorts work to stay open as Covid Cases Snowball: Colorado Sun