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Observation Date
2/4/2015
Observer Name
Toddeo
Region
Salt Lake » Big Cottonwood Canyon » Silver Fork
Location Name or Route
Grizzly Gulch and Silver Fork
Weather
Sky
Few
Wind Direction
Southwest
Wind Speed
Light
Weather Comments
Not as warm as I expected. Still warmer than it should be. Winds mostly felt above 9500'. Some transpaort in this area, minor
Snow Characteristics
New Snow Depth
6"
New Snow Density
High
Snow Surface Conditions
Dense Loose
Melt-Freeze Crust
Damp
Snow Characteristics Comments

Approximately 6" total from the last two "storms". North facing aspects were unaffected by the warm temperatures. South aspects were damp to wet on our ski out at 2.30 pm. Southeast aspects >9500' had a slight crust this afternoon.

New snow is dense and sitting on a variety of surfaces including:

Dry 2-3mm loose facets in thin rocky areas along the LCC/BCC ridge line on North and NE aspects, HS,<60 cm. Hard to isolate the new snow, especially in wind drifted areas.

N and NE aspects with Silver Fork: New snow sitting on top of fist to 2 finger density faceted snow approximately 40 cm thick. The mid-pack in this area appears strong.

South aspects: new snow sitting on suncrust, well bonded, during the morning, before heating, the only real shear I was able to get was with in the new snow on a density inversion at the 3" mark, Q3 and hard, most likely the interface between the two "storms". This settled out with heating during the day.

With the exception of the thin faceted areas, the new snow was easy to isolate with negative ECTs., the new snow just collapsed.

Red Flags
Red Flags
Wind Loading
Rapid Warming
Red Flags Comments
Some wind loading, drifts up to 40 cm thick and nonreactive. Pockety moderate danger. Rapid warming, I think the breeze helped at the upper elevations today, forecasted warm temps tomorrow will be a concern, danger could rise to considerable.
Avalanche Problem #1
Problem
Wet Snow
Trend
Increasing Danger
Problem #1 Comments

Moderate today, could rise tomorrow on sunny aspects. I might also be a bit concerned about some of the north facing terrain if the temps get as warm or warmer than forecasted.

We had one minor slide on a steep south aspect this afternoon. New snow only and the slab released/buckled and only ran a few feet on the suncrust.

Did notice a good sized debris pile below the main gut of SE facing Superior this afternoon. Looked like a possible crown but didn't have binoculars so unsure. Likely skier triggered.

Avalanche Problem #2
Problem
Persistent Weak Layer
Problem #2 Comments

Mostly low danger with pockets of Moderate possible at the upper elevations.

Comments

A lot of sluffing on steeper north aspects today, one in Easy Does It was large enough to knock a skier over, new snow only running on underlaying faceted snow, ran about 200' vertical and faster than expected enough snow moving to warrent me getting out of the way. Other sluffs did not entrain enough snow to be a significant concern. Some were running on the density inversion between the last two "storm" events, this will likely settle out overnight. Sluffing would be something to watch tomorrow in bigger terrain.

Hazard is generally limited to new snow only.

Raised danger from generally low today to moderate tomorrow due to warming temps, could go higher on upper elevation south aspects.

Today's Observed Danger Rating
Low
Tomorrows Estimated Danger Rating
Moderate