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Observation: Big Cottonwood Canyon

Observation Date
3/29/2020
Observer Name
B
Region
Salt Lake » Big Cottonwood Canyon
Location Name or Route
Upper Big Cottonwood
Weather
Sky
Overcast
Precipitation
Light Snowfall
Wind Direction
Southwest
Wind Speed
Light
Weather Comments
Early morning mostly clear skies gave way to OVC by 0930. First squall/wave of snow came in with this initial cloud cover, and intermittent snow showers persisted throughout the day with 1 to 2 inches of accumulations depending on altitude. Temperatures rose today at least 5 to 7 degrees from previous day. Calm SW winds accelerated to high end Light velocities for brief periods during passing short waves, and there was Light Transport observed in the Upper elevations.
Snow Characteristics
New Snow Depth
4"
New Snow Density
Low
Snow Surface Conditions
Powder
Melt-Freeze Crust
Snow Characteristics Comments
East aspects appeared to survive during the past 48 hours of intermittent solar above 9500 feet due to the early morning cold temps and cloud cover. W, S, and SE aspects had various thicknesses of m/f crusts. NW, N, and NE aspects continued to have incredibly good riding for late March, and this recent storm system may have offered the best riding of the year.
As usual for this late in the season, altitude plays a huge part in offering the best cold snow opportunities; and below 8500 feet the snow quality changes drastically.
Red Flags
Red Flags
Recent Avalanches
Rapid Warming
Red Flags Comments
The only Red Flag observed in areas traveled was Loose Dry and confined to only the upper 2 to 4 inches of the latest round of light density snow. Exited backcountry by 1200, and at that point the snow surface had not gotten damp on any aspects due to the cloud cover and early morning cold temperatures. After exiting there were extended periods of FEW sky cover with temperatures warming significantly. As a result, it was likely that there was Greenhousing going on in various areas. Human triggered avalanche reports from the backcountry continue to filter in every day.
Avalanche Problem #1
Problem
New Snow
Trend
Same
Problem #1 Comments
See above regarding Loose Dry. Still able to isolate Easy to Moderate Shears on shady aspects down 8 to 12 inches on clean shear planes, yet no slab issues observed.
Avalanche Problem #2
Problem
Wet Snow
Trend
Increasing Danger
Problem #2 Comments
See above for the likelihood of this problem being an issue later in the day after exiting. Any sustained periods of solar (combined with rising temperatures) will increase the trend for this danger in the future.
Despite no activity observed in areas traveled, Moderate appears to be the correct Danger Rating due to the continual reports of Human Triggeed avalanches in the past 72 hours.
Today's Observed Danger Rating
Moderate
Tomorrows Estimated Danger Rating
Moderate