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Observation: Big Cottonwood Canyon

Observation Date
1/6/2023
Observer Name
B
Region
Salt Lake » Big Cottonwood Canyon
Location Name or Route
Big Cottonwood
Weather
Sky
Overcast
Precipitation
Heavy Snowfall
Wind Direction
West
Wind Speed
Moderate
Weather Comments
S5 snowfall rates in the early am with at least S3 until 1300. Temperatures began winter like and once again rose significantly throughout the morning hours with mid BCC hitting the mid 30's. Moderate Westerly winds vacillating from WSW to WNW were gusting in the Intense category in the Upper elevations.
Snow Characteristics
New Snow Depth
2'
New Snow Density
Medium
Snow Surface Conditions
Powder
Snow Characteristics Comments
Elevation dependent storm totals with HST at 8000' reaching 45cm and Upper BCC easily hitting at least 60cm.
Attempted tour to Back Bowls, and pulled the plug after 100 feet of entering BC, at 0930 HST at least 50cm of upside-down/inverted snow, with 20 cm of four finger plus to one finger slab resting on top of fist plus storm snow, very easy hand shears with cracking; Second option: Lodge shot with 28 cm of rightside-up Storm Snow with no slab, Very slight bottom feeding on a Turning Surface that was a 5 cm spongy/friable m/f crust with four finger minus cold dry snow below, skied well without issues.
Red Flags
Red Flags
Recent Avalanches
Heavy Snowfall
Cracking
Rapid Warming
Poor Snowpack Structure
Red Flags Comments
Poor Snowpack structure confined to Storm Snow and Storm Slab issues. Touchy and Widespread.
Avalanche Problem #1
Problem
New Snow
Trend
Decreasing Danger
Problem #1 Comments
See above for Storm Slab issues, and multiple reports of Catch and Carry validate Widespread sensitivity. With the warm to moderate temperatures on Friday, these issues should be less Reactive on Saturday.
Avalanche Problem #2
Problem
Wind Drifted Snow
Trend
Decreasing Danger
Problem #2 Comments
Contributing Factor of Wind Loading on Friday appeared to exacerbate the Storm Slab Problem. Lingering Wind Slabs on Saturday may still be an issue.
Clear skies and rising temperatures on Saturday may likely help activate any isolated and the few remaining lingering Storm Slab weaknesses, but these should be settled out signifcantly compared to Friday Cycle. The big issue will likely be Wet Loose activity. Supportable bed surfaces on the Solar aspects will help in potentially producing long running sun induced natural avalanches.
Today's Observed Danger Rating
High
Tomorrows Estimated Danger Rating
Considerable