Observation: Big Springs

Observation Date
12/19/2019
Observer Name
Wilson, Covington
Region
Provo » Provo Canyon » South Fork Provo R. » Big Springs
Location Name or Route
Big Springs
Weather
Sky
Clear
Wind Speed
Calm
Snow Characteristics
Snow Characteristics Comments
Short tour up Big Springs, south of Provo Canyon. Elevation was from 5,800’ to 9,600’, we toured primarily valley-bottom and north-through-east facing terrain.
Snow surface is weakening under the clear cold nights, with surface hoar and near surface facets evident. On solar aspects the snow surface was slightly damp, and even true east might be affected with a thin crust.
At 5,800’ the height of snow was generally less than 25cm , and had melted away on solar aspects. At 8,500’ the snow depth was 80cm to 110cm, and in the upper reaches of our tour above 9,000' 120cm was typical.
Red Flags
Red Flags
Poor Snowpack Structure
Snow Profile
Aspect
North
Elevation
9,300'
Slope Angle
29°
Comments
A quick north-facing test pit at 9,250 feet showed a thick slab overlying a weak but strengthening layer of basal facets. Although we got failure down 105cm on 2.5mm facets with elbow-taps in a compression test, we did not get propagation or failure in that layer in an extended column test. The facets were four-finger hardness, showing evidence of some bonding between facet grains. The layer was also very close to the ground, and was thus interrupted by rocks and bushes.
Another party in the area had dug pits on upper elevation east-facing slopes, and reported that they did not find facets at the base. That is, they found a good, stable structure. The lovely ski tracks they left on east-facing avalanche terrain showed us that slope testing hadn’t proved them wrong. Our own exit was a low-angle north-facing slope, and we didn’t check east.
We could see several avalanche crowns in upper elevations, north-west through north facing. We didn’t get into the paths to investigate, but suspect they failed in the 12/14 storm. We didn’t see anything that appeared to have gone into the old snow at the ground.
Today's Observed Danger Rating
Moderate
Tomorrows Estimated Danger Rating
Moderate
Coordinates