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Observation Date: 
12/30/2016
Observer Name: 
Darce Trotter/Steve Cote
Region: 
Skyline
Location Name or Route: 
Big Meadow
Weather
Sky: 
Clear
Wind Direction: 
Southwest
Wind Speed: 
Moderate
Weather Comments: 
widespread evidence of big wind event Dec 28, cornice failures along summit ridges E facing, pulling out some small pockets, but very warm out of the wind. Crossloading, weird patterns, wind slabs way down slopes and in gully bottoms?? all point to evidence from Monument Peak data 40 to 50 mph with gusts near 70 for 8 hours or longer on Dec 28. Temps have risen over freezing the last couple of days up high, again strong inversion the rule today.
Snow Characteristics
Snow Surface Conditions: 
Powder
Wind Crust
Snow Characteristics Comments: 

still very happy with condition of overall pack, but did find older graupel layer still midpack, but could not get it to fail, after prying on it with shovel we did get a Q1 shear down 18" on top of older 1" MF crust.  conditions ranged from wind buffed hard slab that is difficult to even get an edge in and made for tenative skinning, to sheltered snow creamy turns, with rapidly change from zone to zone

Red Flags
Red Flags: 
Wind Loading
Cracking
Red Flags Comments: 
see pics for recent pockets triggered by cornice fall, cornices continue to calve off.
Avalanche Problem #1
Type: 
Cornice
Trend: 
Same
Problem #1 Comments: 

as above

Avalanche Problem #2
Type: 
Wind Slab
Trend: 
Same
Problem #2 Comments: 

all over the place, but not well connected, I believe the term is "spatial variability"

Snow Profile
Aspect: 
North
Elevation: 
9700
Slope Angle: 
25

we got surprised at the density change level, would not fail on ECT but got Q1 shear when we really pried on it

Video: 

typical cornice fall pocket pulling out

this Q1 shear was on top of 1" deteriorating MF crust

Today's Observed Danger Rating: 
Moderate
Tomorrows Estimated Danger Rating: 
Moderate
Snow Profile Coordinates: 
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