Observation: Cutler Ridge

Observation Date
12/29/2024
Observer Name
Derek DeBruin, Dave Leydet
Region
Ogden » Ben Lomond » Cutler Ridge
Location Name or Route
Ben Lomond, Cutler Ridge
Weather
Weather Comments
Fog throughout the valley to a few hundred feet above the trailhead, receding throughout the morning. Increasing clouds throughout the day, with clouds lowering onto summits by 1330 or so. Afternoon precip had yet to start by the same time. Winds at mid/upper elevations were light/moderate and generally out of the SW, gusting moderate/strong, with some snow transport (but rather limited).
Snow Characteristics
Snow Characteristics Comments
Rain/snow line from yesterday (20241228) seemed to sit around 7500ft or so. Surface snow at the trailhead had maybe 7cm of unsupportive surface freeze, with crust thickness diminishing with increasing elevation. Around 7500ft the crust became quite thin, transitioning to a rime crust to at least 8300ft--but based on the riming on nearly every tree above 8000ft, I suspect the rime crust was present much higher as well. At low elevations, snow beneath the crust was damp/moist due to rain. Above the rain/snow line the snow under the crust was certainly not dry, but felt appropriately damp for high density snow.
Red Flags
Red Flags
Recent Avalanches
Rapid Warming
Poor Snowpack Structure
Red Flags Comments
Found no cracking or collapsing in our travels today, in stark contrast to yesterday. Wind loading was occurring, but snow transport was minimal (since the snow surface was coated in rime crust), so limited loading occurred. The snowpack structure is still relatively poor, with ample facets (30-45cm) at the ground, though these are damp and/or rounding. However, the pattern for failures seems to be in the upper pack, at a storm interface. We found this interface to be about 30cm down at 7600ft outside of wind loaded areas (full profile below). CT yielded an easy shear on this interface. Adjacent pits saw ECTP14 down 30cm in one and ECTN29 down 30cm in the other. Below 7000ft there had been plenty of rain, with everything saturated from top to bottom. We found basically no reactivity underfoot or in hand pits. It made for some more demanding skiing on the exit but likely sets us up well for additional snow. Initially high cloud ceiling permitted viewing of the natural avalanche cycle on the Cutler headwall (will submit separate obs for all of these). Also saw another avalanche we triggered remotely yesterday and didn't notice (obs for this one, too). Punchline for these in general are N-NE-E failing on a storm interface due to wind loading--nothing appeared to go to the ground.
Snow Profile
Aspect
North
Elevation
7,600'
Slope Angle
22°
Comments
There's good news and bad news down low. Bad news: there was rain below about 7500ft, with things quite wet and crusty especially below about 6700ft. Photo below is drainage runnels on the Birthday Bowls. The good news: the whole snowpack was wet all the way to the ground and we noted no obvious instability, a good set up for later. HS up to 100cm or so, with rightside up F to 4F and a crust about 30cm above the ground. Boot pen was also 100cm.
In the mid elevations, snowpack was fairly rightisde up (4F +/-) with some spatial variability, particularly in wind affected areas. HS 150cm or more, but in many locations snow was still on 4F hardness and therefore boot pen matched the HS. I think the rime crust prevented wind slab formation throughout the day, but with the afternoon/evening snowfall, I suspect there may be poor bonding with shallow storm/wind slabs failing on this crust.
Coverage and wind affects in the mid/upper elevations.
Photo of Cutler Headwall avalanches (see individual avalanche obs for more info).
Today's Observed Danger Rating
None
Tomorrows Estimated Danger Rating
None
Coordinates