Wayne Flann Avalanche Blog: January 8, 2021

YESTERDAY:

Sunrise was at 08:10 Hrs Thursday.

Overcast with sunny breaks Thursday am.

Great snow on North facing slopes.

Taylor Meadows.

Ipsoot.

Multiple cloud layers Thursday am.

Certainly areas with wind effect.

Thursday January 7, 2021. 15:00 Hrs. -4 with a 10-20 KPH ESE wind. 0 Deg in the valley.

GOES image from Thursday afternoon.

Later in the day.

Weather Observations for January 8, 2021 taken at 06:00 Hours.

2240 meters -7, Winds were 40-45 KPH E--Horstman Hut

2180 meters -6, Winds were 60-75 KPH SE--Whistler Peak
1860 meters -3, Winds were 10-25 KPH W --Rendezvous

1835 meters -4, Winds were 20-40 KPH SE--Round House

1650 meters -3, trace in 12 Hrs, trace in 24 Hrs, Base 239 cm --Pig Alley
1570 meters -4, trace in 12 Hrs, trace in 24 Hrs, Base 151 cm--Catskinner

660 meters -1, Valley Temp, Max temp Yesterday was + 1.3, 0.0 mm of precip yesterday.

As of 07:00 Hrs this am we have overcast skies, limited visibility and snowing lightly.

FORECAST:

A weak slow moving frontal boundary will push through this morning in a Southerly flow aloft. Light precip will taper to flurries by this afternoon with dry cloudy weather for tonight into Saturday in a North Westerly flow aloft. FL will rise to around 1000 m. Weak ridging for Saturday but may only see a few sunny breaks in the morning with a mix of sun and cloud. Another weak front arrives Saturday night into Sunday morning. Flurries Sunday afternoon with a brief drying trend until Sunday night when a front arrives bringing light to moderate precip into Monday. A more active front arrives for Tuesday. Guesstimates: 2-6 cm by Saturday am, 4-8 cm by Sunday am, 3-6 cm by Monday am, 12-18 cm by Tuesday am.

Timing of some of the fronts is difficult on a 24 hr forecast, there has been some significant differences in some of the models.

GOES IR image from this am.

Weak upper trough pushes through this morning, with flurries by this afternoon.

High to the East, Low to the West. On the edge again. Looks unsettled.

Weak front for Sunday with periods of light precip.

AVALANCHE ACTIVITY:

Old activity in Lakeside Centre. AC on Blackcomb yesterday produced limited Sz 1-2 Xh.

Sz 2 on Stuie's from Heli Bombing yesterday. AC on Whistler produced Sz 2-2.5 Xh.

. Activity On Flute.

. You can see the Kees Claire Hut in top right of the image. Sr 20 meters away on the flats. Sz 2.5

Just below the other Fx Line. Sz 2?

Sz 2.5 on the South end of Cowboy Ridge observed Yesterday afternoon.

Close up of the Fx Line. Sr. From South coast touring Mitch Sulkers. Scott Flavell Image?

Fx line from slide above. Scott Flavell Photo?

Sz 3 on Piccillo. Buried the Rock Berm to deflect avalanches from the lift. Building a snow berm.

Down to the Dec 9Th crust. Rebuilding a snow berm may take some time. No damage to the lift.

Phalanx Sz 2.5 slab Xr from 2021-01-06, slid on 2020-12-09 MFcr. Monty Clemens Image

Fracture Line profile from yesterday.

From the Sea to Sky Avalanche Advisory:

Avalanche Summary

On Thursday there was a report of a remotely triggered (from a distance of 20m) size 2.5 deep persistent slab avalanche on a west aspect at 1930 m on Cowboy Ridge. The fracture line was up to 200 cm deep.

On Wednesday there were numerous size 2 explosives controlled storm slab avalanches reported running in the alpine and treeline. As well there were several persistent and one deep persistent slab size 2.5-3 ranging in depth from 100-150 cm.

Reports on Monday and Tuesday show a few explosives controlled storm slab avalanches running size 1-2 as well as a few human triggered storm slab and loose dry avalanches size 1-1.5.

Snowpack Summary

Over 150 cm of recent storm snow from the past week has seen extensive wind effect at upper elevations, with scoured windward aspects, wind slabs in lee features and growing cornices at ridgetop.

The snowpack is currently quite complex. The layer of greatest concern is a melt-freeze crust from early December, found around 100-200 cm deep in the snowpack. This crust may have surface hoar or sugary faceted grains sitting above it. There have been several recent large natural and human triggered avalanches on this layer and new snow loads as well as large loads from storm slab avalanches have potential to trigger these layers.

INFORMATION & OBSERVATIONS:

Awesome light just before sunrise Thursday am. Looking clear to the East.