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Observation Date
4/28/2017
Observer Name
C Brown
Region
Salt Lake » Park City Ridgeline
Location Name or Route
Park City Ridgeline
Weather
Sky
Obscured
Precipitation
Light Snowfall
Wind Direction
West
Wind Speed
Light
Weather Comments
Snowing lightly most of day, cool temps and cloud cover kept the new snow light and fluffy. Few periods of thinner clouds and localized greenhousing. Winds were light but with low density now there was transport and cornice building going on.
Snow Characteristics
New Snow Depth
5"
New Snow Density
Low
Snow Surface Conditions
Powder
Snow Characteristics Comments

Pretty nice snow quality today. Could feel the older denser and wind affected snow underneath the fluff that has been falling recently. This right side up setup kept the skiing bottomless in west monitor and E-NE-N terrain observed today.

Red Flags
Red Flags
Recent Avalanches
Wind Loading
Red Flags Comments
Many of the instabilites observed yesterday seemed to have settled out, at least in the PC side. New soft windslabs had formed and were continuing to grow with the light density wind and the winds along the ridglines. Cornices were growing and new cornice growth was sensitive. Accidently colapsed a decent chuck of soft cornice onto the slope that triggered a 10" deep windslab, about 30'x30' pocket that ran almost full track and entrained the new light snow. Triggered another smaller windslab that was somewhat stuborn and did not run to far. These seemed to be failing on graupel from yesterday.
Avalanche Problem #1
Problem
Wind Drifted Snow
Trend
Increasing Danger
Problem #1 Comments

Somewhat stubborn today but up to about size 1 was triggered from cornice collapse. With this light density new snow and continued light to moderate winds and additional snowfall these could become bigger and become more sensitive, but after storm passes/winds back I would expect these to settle out quick. Manageable problem, but don't want it coming down on top of you.

Avalanche Problem #2
Problem
Cornice
Trend
Increasing Danger
Problem #2 Comments

New soft sensitive cornices are building currently and will continue with the snow for transport and winds. Old cornice are welded, but the new growth is pretty sensitive, and the collapsing cornice is enough to trigger size 1+ wind slabs. Would expect the new growth to start calving naturally overnight, and peel off when the sun hits them.

Comments

Pictures of my cornice triggered wind slab (sorry for poor quality, lighting/vis was bad today)

1) Cornice with new growth and crown from cornice triggered wind slab.

2) WS crown

3) Wind Slab track in w monitor

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