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Observation Date
12/25/2014
Observer Name
Toddeo
Region
Salt Lake » Big Cottonwood Canyon » Mill D North
Location Name or Route
Mill D, Powder Park
Weather
Sky
Obscured
Precipitation
Moderate Snowfall
Wind Direction
Northwest
Wind Speed
Light
Weather Comments
On and Off again snow all day. Light winds on ridgetops, calm below.
Snow Characteristics
New Snow Depth
8"
New Snow Density
Low
Snow Surface Conditions
Powder
Snow Characteristics Comments

8-10"new, Thanks Baby Jesus!

1" new at the spruces during the day (5 hours) and at least 2" at 9000+' feet during this time period.

Upper 4" or so is low density stellers and clumps of stellers. Bond is good on all aspects skied/tested at elevations ranging from 7400 to 9400'. Ski cut a couple of 35 degree rollovers without significant sluffing. If this storm came in on a stable base, it would be green light conditions, but it did not.

With the exception of shallow s/SW facing areas (e.g. HS<70 cm) upper and mid-pack are easy to isolate. Shallow SW and SW aspects are hard to isolate, fail upon isolation in low density fragments above a crust.

On west and NW aspects:

All ECTs' were ECTN (20+) failing at/or near the base of the last snow event. This break is stubborn but does have a relatively clean shear, Q2 with a good push. Similar to what I saw in Beartrap 2 days ago. HS in the powder park area is over 1 meter.

West Desolation Ridge: Drifts up to 3" deep on the ridge (more wallowing than expected). Minor soft cracking. less than expected. Did not see any signs of past activity as Bret reported. This area may have filled back in (looked fat).

Red Flags
Red Flags
Heavy Snowfall
Wind Loading
Collapsing
Poor Snowpack Structure
Red Flags Comments
Heavy snow at times although low density may not add significat weight to the snow pack. Low to moderate hazard. Drifts up to 2' deep on ridge tops, mostly from the beginning of the storm, last 4" came in with very little wind. Drifts seemed nonreactive. Low to moderate hazard. Minor collapsing on south aspects, mostly due to air pockets/bushes, I believe, no associated cracking. Poor snowpack structure is still there in both shallow and deeper areas. This is likely of the greatest concern.
Avalanche Problem #1
Problem
New Snow
Trend
Decreasing Danger
Problem #1 Comments

New snow from the last two events. Moderate hazard

Avalanche Problem #2
Problem
New Snow
Trend
Same
Problem #2 Comments

This is still lurking, probability is likely only moderate but with significant consequences.

Comments

Overall danger a hard call, I think it depends on how the consequences are weighted. I am treating the north 1/2 of the compass as considerable.

Coverage is still poor for this time of year, much wood exposed and lurking near the surface, cone flowers are still way too tall!

Moderate hazard on the south 1/2 of the compass.

On north aspects, I am calling the hazard considerable due to consequences.

Happy Holidays!

Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
Considerable