Observation: Big Meadow

Observation Date
12/30/2016
Observer Name
Darce Trotter/Steve Cote

Region:

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