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Observation: Mineral Basin

Observation Date
1/9/2019
Observer Name
B
Region
Salt Lake » Little Cottonwood Canyon » Snowbird Ski Resort » Mineral Basin
Location Name or Route
Lower Mineral Basin
Weather
Sky
Overcast
Wind Direction
Southeast
Wind Speed
Moderate
Weather Comments
Early morning overcast skies gave way to few by early afternoon. Temperatures were unseasonably warm with a lack of refreeze noted from 8000 to at least 9500. Moderate SE winds veered in the afternoon to be out of WSW. Moderate wind blown and or transport observed on exposed ridge lines in the upper elevations.
Snow Characteristics
Snow Surface Conditions
Dense Loose
Wind Crust
Melt-Freeze Crust
Damp
Snow Characteristics Comments
Mondays winds created dense surface and sub-surface snow conditions, and the warm temperatures on Tuesday combined with these windy conditions to help bring on at least 25% settlement in the abundant snow fall from the weekend. HSN has now shrunk to 50 cm at 9500 feet in shady terrain. In all but except the most sheltered terrain, when turning you were only carving into tghe upper 15 cm. In more exposed terrain the snow surface was dense, wind packed and one finger to pencil hard. Afternoon solar continued to warm the snow surface on S and SW aspects with slope angles 25 degrees and greater, yet there didn't' appear to be any new significant wet loose activity in the upper elevations.
Red Flags
Red Flags
Recent Avalanches
Wind Loading
Poor Snowpack Structure
Red Flags Comments
The southerly winds were transporting significant snow on all the upper elevation onto NW, N, N and NE facing terrain. Poor snowpack structure noted at 9700 feet on north aspects with the 1/5 interface (pre-frontal) having well developed small facet grains. Hasty pits and hand shears were yielding easy shears 50 to 60 cm down. The dense snow from the weekend appears to be consolidating and becoming a more cohesive dense/stiff slab. Avalanche activity (D2) from the weekend observed in upper Mary Ellen Gulch in Silver Creek Bowl as well as 4th of July Bowl.
Avalanche Problem #1
Problem
Wind Drifted Snow
Trend
Increasing Danger
Problem #1 Comments
See above, and with the winds appearing to not be loosing strength, this problem may be increasing overnight.
Avalanche Problem #2
Problem
Persistent Weak Layer
Trend
Same
Problem #2 Comments
Persistant Slab concerns appear to be possible at three distinct layers. The previously cited 1/5 pre-storm interface appears to be the most likely. There is also the mid December interface that may be lingering in some shallower snowpack locations as well as basal facets in steep/thin/rock/shady snowpack areas.
Today's Observed Danger Rating
Moderate
Tomorrows Estimated Danger Rating
Moderate