Observation: Snowbasin Backcountry

Observation Date
12/8/2015
Observer Name
Kory
Region
Ogden » Snowbasin Backcountry
Location Name or Route
Snowbasin area
Weather
Sky
Scattered
Wind Direction
Southwest
Wind Speed
Moderate
Weather Comments
Very warm day. Not sure what the snow line was last night but temps were in the low thirties all morning.
Snow Characteristics
New Snow Depth
3"
New Snow Density
High
Snow Surface Conditions
Powder
Wind Crust
Damp
Snow Characteristics Comments

New snow was very heavy.

Red Flags
Red Flags
Collapsing
Rapid Warming
Poor Snowpack Structure
Red Flags Comments
Today I had a few collapses in areas around 8,300 ft. Above that elevation the new snow was to soft and not well connected to get collapses. I did try and find the culprit layer but it seems there are two.
Avalanche Problem #1
Problem
Persistent Weak Layer
Trend
Increasing Danger
Problem #1 Comments

I was surprised with the collapsing today. I was not expecting to have that well of a connected slab. I think that in areas where snow has piled up you could trigger an avalanche deeper now on the weak facets at the ground.

Avalanche Problem #2
Problem
Wet Snow
Trend
Same
Problem #2 Comments

With the wet snow on facets you could trigger a wet slide today in the right area.

Snow Profile
Aspect
East
Elevation
8,400'
Slope Angle
24°

Photo 1. Area where I had the largest collapse all the way up to the rocks in the photo. Most collapses happened in similar terrain.

Photo 2. Thought to be culprit layer of collapse. Pretty sure this is the surface hoar from the cold nights before this rain/snow event if not maybe just some near surface facet growth but still very reactive.

Photo 3. Quick hand pit in one of the areas where had a collapse. Upper layer I believe to be the surface hoar, Lower layer was just good old basel facets.

Photo 4. In the right areas there is a lot of snow in the Ogden mountains. I was looking for the layers in a little deeper spot but seemed to of found too much snow. I did want to look in these areas because they are really the only areas you can ski (where snow is deep enough)

Photo 5. ECT X in the deeper pit but with a very gentle pull with the hand it popped out very nicely and in Q1 fashion on the Surface hoar layer.

Photo 6. As always in the mountains the light did not cooperate on a photo of the facets that failed.PhotS

Photo 1 Birch Creek Snow cover

Photo 2. More represetitive snowpack in the Ogden mountains at about 8700 feet. Fist from 0-28cm and four fingers of new wet snow from 28-37cm. The 0-28cm facets were a mix of 2-4mm big. These facets were wet though from the warm temps. You could make a snowball out of them. The new now was not cohesive enough to get any results in snowpit tests.

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