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Observation: Weber Canyon

Observation Date
1/21/2018
Observer Name
B
Region
Uintas » Upper Weber Canyon » Weber Canyon
Location Name or Route
Western Uintas: Weber Canyon Area
Weather
Sky
Overcast
Precipitation
Light Snowfall
Wind Direction
Northwest
Wind Speed
Moderate
Weather Comments
Overcast skies gave way to few later in the day. Temperatures remained cold throughout the day and never got above the middle teens. Winds were in the high end of the light range most of the day with occasional periods of moderate out of the NNW. Wind blown and or transport was moderate at times even on the mid elevation ridgelines. Sporadic periods of snow showers at S minus 1.
Snow Characteristics
New Snow Depth
15"
New Snow Density
Low
Snow Surface Conditions
Powder
Wind Crust
Melt-Freeze Crust
Snow Characteristics Comments

Along the ridge lines on some exposed northerly facing terrain the winds had stripped all the snow down to the prestorm m/f surface layer. Cross loading and top loading were evident again even at mid elevation ridgelines, and four finger wind slabs up to 2 feet deep were observed. On the leaward side of easterly running ribbed terrain features there were wind deposits that were one finger and these were avoided. Excellent powder riding in many locations including northerly, southerly and easterly aspects. The riding on the southerlies were table top riding in 12 to 15 inches of light density snow.

Red Flags
Red Flags
Recent Avalanches
Wind Loading
Cracking
Poor Snowpack Structure
Red Flags Comments
Insignificant cracking in the new snow was observed and this appeared to be occuring in a reactive storm snow layer 6 inches down. See above for wind loading, and it was very likely that the upper elevations were experiencing more widespread loading and larger wind deposits/slabs on similar aspects. Two small wind slab related avalanches were observed on E and SE aspect from cross loading, and these appeared to have occurred late in the day on Saturday. Poor snowpack structure was still observed on NW, N, E and SE aspects, yet multiple hasty pits indicated there was some rounding going on both in the mid pack weak layers as well as in the basal facets. Despite these signs of the pack slowly healing and turning around, hand shears were easily yielding clean shears in the mid pack weak layers; and the basal facets are still cohesionless. Also of note were the observations indicating NSF's at the new snow/old snow interface on sheltered mid slope NE aspects. Finally some easterly had facets above and below the friable prestorm m/f crust that was the prestorm snow surface.
Avalanche Problem #1
Problem
Wind Drifted Snow
Trend
Increasing Danger
Problem #1 Comments

See above, and the more than ample amount of snow available for transport along with the forecast calling for increasing SW winds on Monday, this problem may escalate.

Avalanche Problem #2
Problem
Persistent Weak Layer
Problem #2 Comments

As a result of the load possibly increasing on the N and NE aspects due to wind transport, the previously mentioned PWL's and poor snowpack structure has a possiblility of becoming reactive in isolated locations on steep slopes. These kinds of slopes appeared to not have enough load to be a problem today, yet with the poor snowpack structure still in place this concern has definitely not gone away.

Loose snow dry avalanching and sluffing was also obseved on steep protected southerly slopes.

In the areas traveled today the danger appeared to be Moderate, and if the winds don't complicate things too much on Monday they may remain Moderate; yet if and when the winds begin to enhance loading the danger may rise to Considerable.

Today's Observed Danger Rating
Moderate
Tomorrows Estimated Danger Rating
Moderate