Details

• Date: 2013/01/15

• Observer: Zach Guy

Location

• BC Zone: Gunnison
• Area Description: Elk Mtns near Copper Creek
• Route Description: Near Mt. Avery. 10,000-13,000 ft.

Weather

• Ridgeline Wind Speed: 10-20 mph
• Ridgeline Wind Direction: NW
• Wind Loading: None
• Sky Cover: Clear

Snowpack

• Snowpack Description: Above treeline surfaces are variable from hard slab to facets and sastrugi. No surface hoar observed on any slopes, just valley bottoms.

Snowpack Obsvervation #1 Persistent Weak Layer: Yes Comments: HS ~60cm. All faceted snow, Fist down to 4F at the bottom, in general. MF crust developing on surface with facets above.

Snowpack Obsvervation #2 Cracking: Shooting Collapsing: Moderate Persistent Weak Layer: Yes Comments: Scoured to shallow faceted snow near ridgelines. Lower on slopes, isolated pockets of hardslab, easy to identify. 6-12" deep above faceted snow to the ground. Several old R1D1.5 slides originating from these pockets. Elsewhere the snowpack is almost entirely faceted with textured sastrugi features. One skier triggered collapse while traversing just above a slab.

Snowpack Obsvervation #3 Cracking: Shooting Persistent Weak Layer: Yes Comments: Widespread 4-8" hardslabs from ridgelines to far down on slopes. Some pre-existing cracks and a skier triggered crack. MF crust forming only on steep S and SW aspects >40 degrees

Snowpack Obsvervation #4 Cracking: None Collapsing: None Persistent Weak Layer: Yes Comments: MF crusts on all slopes, even low angle. Mostly faceted snow below. No signs of instability on steep terrain.

Avalanches

	Date	Location/Path	#	Elev	Asp	Type	Trig	SizeR	SizeD
	2013/01/15  †	Gothic	1	>TL	SW	HS	N	R2	D2
Date: 2013/01/15 (Estimated) Observer: Zach Guy Area Description: Rustler's Gulch Landmark: Gothic Elevation: 12600 ft Sliding Surface: O - Within Old Snow Weak Layer: Unknown Average Width: 700 ft Average Vertical: 1500 ft Comments: Surprisingly large for just new windloading; may have stepped through older snowpack
	2013/01/11  †	Gothic	1	>TL	N	HS	N	R1	D1.5
Date: 2013/01/11 (Estimated) Observer: Zach Guy Area Description: Near Avery Mtn Landmark: Gothic Elevation: 11600 ft Sliding Surface: O - Within Old Snow Weak Layer: Layer Weak Layer Grain Type: Faceted Crystals Average Crown: 18 in Average Width: 100 ft Average Vertical: 300 ft Comments: Old slides. Likely failed on Nov/December facets, which aren't buried too deep in this zone.
	2013/01/15  †	Gothic	2	>TL	E	SS	N	R1	D1
Date: 2013/01/15 (Estimated) Observer: Zach Guy Area Description: Mt Baldy Landmark: Gothic Elevation: 12400 ft Sliding Surface: I - New/Old Interface Weak Layer: Layer Weak Layer Grain Type: Near Surface Facets Average Crown: 12 in Maximum Crown: 16 in Average Width: 150 ft Average Vertical: 1200 ft Comments: Estimated from a distance
	2013/01/15  †	Gothic	1	>TL	SW	HS	N	R1	D1
Date: 2013/01/15 (Estimated) Observer: Zach Guy Area Description: Cassi Peak Landmark: Gothic Elevation: 13000 ft Sliding Surface: I - New/Old Interface Average Crown: 6 in Maximum Crown: 10 in Average Width: 150 ft Average Vertical: 900 ft