Observation: Moab

Observation Date
2/11/2024
Observer Name
Trenbeath
Region
Moab
Location Name or Route
Laurel Highway to Pre-Laurel Peak-Gold Basin
Weather
Sky
Clear
Wind Direction
Northeast
Wind Speed
Light
Weather Comments
Bluebird winter day with cool temps and light winds after an off and on, 10 day stormy period.
Snow Characteristics
Snow Surface Conditions
Powder
Damp
Snow Characteristics Comments
Excellent powder conditions after nearly 3' of snow and 3.0" SWE since Feb 1. The final significant accumulation was 8" on Feb 9. A squall on the afternoon of the 10th put down a trace. Light to moderate NE winds moved some snow around up high but we observed no slab formation on leeward slopes at 11,700'. We skied primarily southerly aspects and found generally stable conditions. Strong sunshine dampened the snow surface on southerly exposures, and they will likely be crusted over tomorrow.
Red Flags
Red Flags
Recent Avalanches
Poor Snowpack Structure
Red Flags Comments
The spate of recent avalanche activity is the most obvious red flag but the last round occurred on Feb 7. A significant cycle also occurred on Feb 2. Most avalanches have been above treeline on slopes facing NW-N-E but one large slide was observed on a west aspect. A few have occurred near treeline on northerly aspects, and two have been observed below treeline including one, unique avalanche on a westerly aspect (see the report from Dave Garcia linked below). A few avalanches observed have involved new and wind drifted snow, but most have been nearly full depth releases down to basal facets. Basal facets are alive and well. In deeper areas, they are covered by 100 cms or more, but in shallow areas still less than a meter of snow exists on top.
Avalanche Problem #1
Problem
Persistent Weak Layer
Trend
Decreasing Danger
Problem #1 Comments
Basal facets remain the primary concern, especially in shallower snowpack areas. We also don't know if facets remain in paths that have run. Weaker layers have been observed higher up in the snowpack but as of yet, we've not determined that they are widespread. Avalanches on basal facets are becoming harder to trigger but deep and dangerous avalanches are still possible. We'll soon be moving into a lower likelihood, high consequence scenario.
Snow Profile
Aspect
West
Elevation
10,400'
Slope Angle
27°
Comments
I dug the snowpit profiled above on a west aspect to gain more information based on an avalanche previously observed by Dave Garcia. Westerly aspects have been a bit of a wild card this season. I located a similar, but non-reactive weak layer that produced this avalanche. Results were ECTX even on the basal facets. It was dug at about the same elevation and about a quarter mile up canyon. I also dug a pit on a WSW aspect several hundred feet higher. A stout crust/facet combination exists below the snow that fell over the past 10 days. An ECT produced no results.
I'm adding this photo of an avalanche on the north face of Mount Mellenthin that I observed during GCSAR training Saturday, Feb 10, just because I haven't documented it yet. And it's a cool photo ;) It's hard to see, but the crown runs all the way down to the lower shoulder of the ridge on the observer's right.
Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
Considerable
Coordinates