Observation: Ben Lomond

Observation Date
3/13/2022
Observer Name
Gagne/Frey/Johnston
Region
Ogden » Ben Lomond
Location Name or Route
Cutler Ridge / Cutler Basin
Weather
Sky
Obscured
Precipitation
Moderate Snowfall
Wind Direction
West
Wind Speed
Moderate
Weather Comments
Typical weather associated with an arriving cold front: dropping temperatures, winds shifting from southwest to northwest around 2 pm with two separate rumbles of thunder.
Snow Characteristics
New Snow Depth
2"
New Snow Density
Medium
Snow Surface Conditions
Powder
Wind Crust
Damp
Snow Characteristics Comments
~5 cms of damp snowfall that bonded well to the old snow surface. Some wind drifts found at mid and upper elevations. Below ~7K the upper ~30 cms of the snowpack was damp on all aspects.
Red Flags
Red Flags
Poor Snowpack Structure
Avalanche Problem #1
Problem
Persistent Weak Layer
Trend
Same
Problem #1 Comments
Dug a few detailed pits with several quick pits and pole probes. The PWL is down 15-60 cms (6" - 24") on northerly aspects with a variety of slab thicknesses on top. All pits were ECTX (no fracture of extended column test) or ECTN with 20+ taps. One compression test did get CT 22 down 45 cms on the layer of Jan/Feb facets, but all others were CTN (no fracture).
Despite jumping on all sorts of suspect slopes, no collapses or cracking.
At lower elevations (below 7,000') there are some dry facets underneath stout melt/freeze crusts and it is possible an avalanche could fail more deeply on the PWL.
Comments
Despite the lack of in-your-face instabilities (avalanches, collapsing, cracking, unstable pit results), the poor snowpack structure of a buried PWL with a stronger slab on top kept us off of steeper slopes facing northwest through east. This snowpack structure is concerning and it can't be trusted. I feel there are isolated areas where a 1-2'+ deep slab could be triggered if a rider hit the right spot on the slope.
The good news is that the storm snow from late this past week plus on Sunday morning is providing great riding conditions on slopes above about 7,000' so there are excellent options without committing to steeper, northerly-facing slopes where the PWL resides.
Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
Considerable