Check out our Holiday Auction - Sign Up for the Utah Snow and Avalanche Workshop (USAW)

Observation: Brighton Perimeter

Observation Date
5/6/2023
Observer Name
B
Region
Salt Lake » Big Cottonwood Canyon » Brighton Perimeter
Location Name or Route
Brighton Periphery
Weather
Sky
Scattered
Wind Direction
South
Wind Speed
Calm
Weather Comments
Second overnight period of freezing temperatures. Cloud cover dissipated throughout the morning and early afternoon hours. Temperatures Rose Rapidly and by 1000 hours they were in the 40's.
Snow Characteristics
New Snow Depth
4"
New Snow Density
High
Snow Surface Conditions
Powder
Melt-Freeze Crust
Damp
Snow Characteristics Comments
Before 1000 hours the new snow remained cold and dry, but the overall warmth that was housed in the snowpack continued to vent out and the depth of the new snow shrunk quickly and dramatically. Initially there was up to 15 cm of new snow resting on the dirty old snow interface. Riding was good on moderate and low angle slopes with the steeper terrain allowing the turns to be more "skittery". Despite this, the spongi-ness of the old snow surface provided a solid and good edging surface on the steeper slopes. By 1130 all slopes and aspect below 9500 feet became saturated/wet and were grabby.
Of Note: Due to the extremely warm temperatures from earlier in the week Saturated Grains/Isothermal conditions could be observed at least 30 cm down on all aspects and elevations up to 10300; and in many locations these Wet Grains were 60 cm down. Around any heat gathering sources, these conditions were at least a meter or more down.
Red Flags
Red Flags
Recent Avalanches
Rapid Warming
Poor Snowpack Structure
Red Flags Comments
Widespread Wet Loose Natural Avalanches were observed on many aspects and elevations in steep terrain. Significant Glide Cracks were observed in slabs on the Mary Chutes. After two good overnight refreezes, the stability appeared to be improving. Of Note: The previously cited Wet Grain Poor Structure may come into play over the next 72 hours. There may be a period over the next few days when these same overnight refreezes may allow for the potential for "Corn Slab" Collapsing and Avalanching during periods of daytime heating.
Avalanche Problem #1
Problem
Wet Snow
Trend
Increasing Danger
Problem #1 Comments
See above.
Avalanche Problem #2
Problem
Cornice
Trend
Same
Problem #2 Comments
There are many ridgelines housing large sagging Cornices.
Today's Observed Danger Rating
Moderate
Tomorrows Estimated Danger Rating
Moderate