Wayne Flann Avalanche Blog: February 3, 2021

YESTERDAY:

Just about there, 1 Hour to upload.

There were some breaks in the am.

Amazing where snow will accumulate.

Surfing, the powder was a bit on the dense side!

Anticipation!!!

There were lots of good turns to be had without standing in lines!!

Setting the skin track.

Tuesday Feb 2, 2021. 14:00 Hrs. -6 with a 5-10 KPH West breeze. +1 in the valley. Snowing lightly.

Satellite image from the same timeframe.

Skier Compaction!!!

Cornices are getting very large.

Powder to the People!!

Weather Observations for February 3, 2021 taken at 06:00 Hours.

2240 meters -11, Winds were 10-15 KPH NNE--Horstman Hut

2180 meters -11, Winds were 20-30 KPH N--Whistler Peak
1860 meters -9, Winds were 15-20 KPH N --Rendezvous

1835 meters -9, Winds were 5-10 KPH N--Round House

1650 meters -8, 2 cm in 12 Hrs, 5 cm in 24 Hrs, Base 266 cm --Pig Alley
1570 meters -8, 2 cm in 12 Hrs, 4 cm in 24 Hrs, Base 200 cm--Catskinner

660 meters -3, Valley Temp, Max temp Yesterday was +0.7, 6.3 mm of precip yesterday.

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

FORECAST:

A ridge of high pressure will bring sunny skies in a North Westerly flow aloft. The FL should hover around or slightly above surface. Cloud will begin to push in this afternoon as the next weather system pushes down the coast. Thursday will see periods of light precip all day easing off with flurries by early Friday morning. Ridge rebuilds for Friday with a mix of sun and cloud. Another weak weather system for Saturday with periods of light precip into Sunday. Models are not agreeing with the weekend, chance it may dry out, time will tell. More on that in tomorrow's post. Dry weather expected early next week. Guesstimates: Trace to 2 cm by Thursday am, 4-8 cm by Friday am, 0-trace by Saturday am, 2-6 cm by Sunday am.

GOES IR image from this am.

Ridge building for today. Cold air to the East.

Short lived ridging for today.

Front pushes through Thursday with moderate winds, light precip.

Weak ridging for Friday with a mix of sun and cloud. Cold air just to the East.

AVALANCHE ACTIVITY:

Three ski tourers feared dead in massive avalanche near Silverton, CO. Article below. Net Pic

More info on two fatal avalanche accidents in Stubai Alps. Article below. Net Pic

Recent fracture line from France. Verbier Ski Patrol Pic

Sz 1 Sa Sc??? Feather Tree.

Avalanche mitigation on Blackcomb produced Sz 1-1.5 soft slabs Xe Sc.

A few holes Xl. Avalauncher in Lakeside Bowl.

Avalanche mitigation on Whistler produced Sz 1-2 storm slabs Xe, Xc, Xl. Sz 1-2 Na Va soft slabs.

From Sea to Sky Avalanche Advisory:

Avalanche Summary

Avalanches are expected to remain easy to trigger on Tuesday in many areas, especially in wind loaded terrain at higher elevations.

There have been reports of size 1-2 natural, human and explosives triggered avalanches every day since Saturday. Many of these avalanches have failed on the recently buried persistent weak layer.

Snowpack Summary

50-100 cm of recent fresh snow sits on a persistent weak layer that consists of facets at upper elevations, surface hoar in sheltered areas, a melt-freeze crust below 1900 m, and a sun crust on south-facing slopes. There could be more than 100 cm on this layer in wind loaded areas.

A crust from early December may be found around 200+ cm deep in the snowpack. In shallow rocky areas, it may still be possible to trigger this layer. In deeper snowpack areas, it appears to be unreactive.

INFORMATION & OBSERVATIONS: