Ad
The National Forest Service Logo
icon-add Observation
Forecasts
Logan Ogden Salt Lake Provo Uintas Skyline Moab Abajos Weather Archives How to read the forecast
Observations & Avalanches
Submit Observation Observations Explorer All Observations Avalanches Fatalities Weather Place Names Map Archives
Education
Avalanche Class List UAC Class List Online Classes Resources and Tutorials Avalanche Awareness Develop Skills
Events
Store
About
Contact Who we are Core Values Staff Board of Directors Past Forecasters Sponsors Annual Reports Sign In
Blog
icon-add Observation
Donate / Join

Observation: Ogden

Observation Date
12/9/2016
Observer Name
Derek DeBruin
Region
Ogden
Location Name or Route
Mount Ogden, Strawberry
Weather
Sky
Obscured
Precipitation
Moderate Snowfall
Wind Direction
Southeast
Wind Speed
Moderate
Weather Comments
Relatively warm morning with temp of 28F at 6600' when we left the car around 5:45, up to 36F when we returned around 10:00. Temp at 8500' high point was 23F. Winds were consistently light and increasing to moderate above about 7500', from S, SE, and E. We spent most of the tour in whiteout with limited visibility, though clouds broke briefly around 9:30. Consistent graupel throughout, with rates up to S2 and snow density decreasing with elevation. Saw some snow transport but no evidence of recent wind loading.
Snow Characteristics
New Snow Depth
4"
New Snow Density
Medium
Snow Surface Conditions
Dense Loose
Wind Crust
Snow Characteristics Comments
Approximately 10cm new snow. Soft snow pack at lower elevation, with avg. ski pen. of 20 to 30cm, sometimes at much as 60cm, which made for arduous skinning. Boot pen. at high point was 80cm. Any wind exposed area such as ridges and knobs were solidly windpacked with the fresh snow on top. Upper elevations in general obviously had more windpack or otherwise stronger underlying snow with smaller ski pen. of 10 to 30cm. Density obviously changed with elevation with somewhat moist (could make a snowball with effort) powdery turns initially leading to increasing wet and heavy snow as we neared the trailhead. We dug a north aspect in search of potential basal facets and did not find any. The snowpack was quite rightside up with 1F snow at the base progressing to F at the surface. Much of the mid and lower portions of the snowpack were rounds or rounding with the graupel layer at the mid snowpack beginning to disappear.
Red Flags
Red Flags
Heavy Snowfall
Wind Loading
Collapsing
Rapid Warming
Poor Snowpack Structure
Red Flags Comments
A litany of red flags. Consistent snowfall throughout the morning with potential for wind to move the snow plus prior wind loading. Current warm temps with anticipated rising rain/snow line make me concerned for the potential effects on the snowpack structure through the weekend. We had a small, localized collapse this morning while skinning just beneath a steep 3 meter tall rollover. Otherwise, the snowpack seemed fairly stable. Visibility was too poor to assess any recent avalanche activity.
Avalanche Problem #1
Problem
New Snow
Trend
Increasing Danger
Problem #1 Comments
Tests revealed a CT6 Q2, CT11 Q3, and ECTP13 Q1 25cm deep. This was below the new/old snow interface in what was a fairly consistent layer of wind affected snow (though not exceptionally hard packed). As the storm snow continues to pile on, I imagine this weakness could result in avalanches, if not natural, then human triggered.
Avalanche Problem #2
Problem
Wind Drifted Snow
Trend
Increasing Danger
Problem #2 Comments
We were still 500 to 1000' below the ridgelines, but local knowledge tells me that wind could be a significant concern throughout this storm.
Snow Profile
Aspect
North
Elevation
8,500'
Slope Angle
28°
Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
High
Coordinates