Observation: Moab

Observation Date
1/8/2019
Observer Name
Brian Hays
Region
Moab
Location Name or Route
Laurel HWY
Red Flags
Red Flags
Recent Avalanches
Heavy Snowfall
Wind Loading
Cracking
Collapsing
Rapid Warming
Poor Snowpack Structure
Avalanche Problem #1
Problem
New Snow
Trend
Decreasing Danger
Problem #1 Comments
The new snow from Sunday’s storm formed a dense and cohesive slab at most elevations and aspects except for exposed areas that were wind blasted during the storm. It looked and felt like someone spray coated the mountains with dense styrofoam insulation. The new snow formed a 20-30cm slab on top of a house of cards of underlying older, faceted snow. Signs of instability were blatantly obvious: natural avalanches, frequent collapsing, shooting cracks, and easy failures on test slopes.
Avalanche Problem #2
Problem
Persistent Weak Layer
Problem #2 Comments
The snowpack under the storm snow slab is largely loose, unconsolidated, and faceted. The storm snow easily slides on this substrate.
Comments
Exciting day to be in the mountains. We were originally planning to go bigger but dialed down the plans quickly as we observed an avalanche on the north facing road cut above the trans la Sal trailhead and numerous other signs of instability on the skin up: collapsing, shooting cracks, slides on test slopes. The touchiest snow I’ve experienced in the La Sals. Loads of energy out there. We probably experienced 100 collapses throughout the day (Laurel HWY, North Woods, Julie’s Glade).
Forecaster comment: Excellent observation. Thoughts on Considerable vs High danger rating - generally speaking, a high likelihood for natural avalanche activity is usually required for a high danger rating which wasn't really the case today. On the other hand, if human triggered avalanches are certain, which they were today, that also constitutes a high danger rating. The bottom line is that it is sometimes difficult to compartmentalize complex phenomenon into a single term. Either way, the signs of hair trigger instability are clear - it's dangerous out there!
Today's Observed Danger Rating
High
Tomorrows Estimated Danger Rating
Considerable
Coordinates