Wayne Flann Avalanche Blog: January 16, 2021

YESTERDAY:

Unsettled in the am.

Valley cloud.

You can always find some good turns somewhere!!

Good day in the park!!

Flank on Fissile.

There was some great grooming on Friday.

Friday Jan 15, 2021. 14:00 Hrs. -4 with a 20-35 KPH SW wind. +4 in the valley.

GOES image from the same timeframe.

Mid mountain cloud.

Just before dusk.

Weather Observations for January 16, 2021 taken at 06:00 Hours.

2240 meters -8, Winds were 5-10 KPH S--Horstman Hut

2180 meters -6, Winds were calm KPH S--Whistler Peak
1860 meters -5, Winds were 0-5 KPH S --Rendezvous

1835 meters -5, Winds were 0-5 KPH ESE--Round House

1650 meters -4, 0 cm in 12 Hrs, 0 cm in 24 Hrs, Base 233 cm --Pig Alley
1570 meters -4, 0 cm in 12 Hrs, 0 cm in 24 Hrs, Base 165 cm--Catskinner

660 meters 0, Valley Temp, Max temp Yesterday was + 5.3, 1.4 mm of precip yesterday.

As of 07:00 Hrs this am we have overcast skies and unlimited visibility.

FORECAST:

Weak upper level ridge and low moving down the coast will bring mostly overcast skies in a Westerly flow aloft this am. Hopefully it delivers, last one blew through with no goods. Freezing level will hover around 1000 meters with light precip starting around 15:00 Hrs. Precip will turn to flurries before day break on Sunday. An upper level ridge will bring mostly cloudy skies for Sunday with the low still on the edge of the high. Monday the ridge strengthens with sunny skies expected. We may see some more light precip on Tuesday before entering a dry overcast weather pattern. More on that later! Guesstimates: 4-8 cm by Sunday morning, 0 cm by Monday morning, 0 cm by Tuesday am.

GOES IR image from this am.

High pressure will give way to the low with light precip by this afternoon.

There is some moisture heading our way.

High pushes back on Sunday.

High strengthens for Monday.

AVALANCHE ACTIVITY:

Natural cycle in Poop Chutes from Wednesday's storm.

Old Na from storm on Wednesday. Blackcomb Glacier.

Na Sz 3 from Wednesday.

Very active cycle on Wednesday.

Roof avalanche.

No new avalanche activity observed on Blackcomb.

Limited AC on Whistler 1 Sz 2 cornice drop, 1 Sz 1 windslab. Xe Xc

From Sea to Sky Advisory:

Avalanche Summary

Explosive control work targeting cornices on Friday produced results up to size 2. On Wednesday, there were reports of a natural storm slab avalanche cycle up to size 3. There were also several that stepped down to deeper weak layers resulting in very large (size 3-4) persistent slab avalanches. Check out this MIN describing a large cornice-triggered avalanche in the Blackcomb sidecountry on Thursday.

Last Saturday, a large (size 3) avalanche was remotely triggered by skiers on Cowboy Ridge near Whistler. The avalanche occurred on a north to northwest aspect at around 1900 m. The crown ranged reached up to 200 cm and was approximately 200 m wide. Check out this MIN for photos and more information. A similar avalanche was remotely triggered by skiers on a nearby westerly slope a few days before; check out this MIN for more info and photos.

Snowpack Summary

Variable wind effect in the alpine includes scoured windward aspects, sastrugi, hard slab, wind pressed surfaces over lower density snow and isolated pockets of soft snow in sheltered areas above 2000 m. Wind slabs may remain sensitive where they overlie surface hoar in sheltered terrain or a crust on solar aspects. A widespread surface crust exists below 1900 m.

The snowpack is currently quite complex. Layers of surface hoar as well as sugary faceted grains above a hard melt-freeze crust from early December may be found down 100 to 200 cm. Last weekend, several large natural and human-triggered avalanches on this layer occurred, with the hot spots being around the Whistler backcountry.

Near the base of the snowpack, there may be faceted grains above a crust from early-November, which was identified as the failure layer in recent sporadic avalanche releases. At this depth, avalanches are large and destructive.

INFORMATION & OBSERVATIONS:

Adventure Smart will be at the Bottom of Blackcomb Gondola for Avalanche Awareness Days.