Snowpack Structure Higher up in South Lake Drainage

SNOWPACK OBSERVATION
Brown Lake Gully
Submission Info
Tuesday, February 2, 2021 - 2:30pm
Red Flags: 
Recent loading by new snow, wind, or rain
Brown Lake Gully 37° 9' 49.0968" N, 118° 32' 18.744" W
Snowpit Observations
More detailed information about the snowpack: 

Dug a pit at 11,400 on a NNE ascpect today in the Green Lake drainage and found some confidence inspiring snow! We dug about a third the way up the gully above Brown Lake.

Snow depth was 1 meter deep. The top 15cm was two different wind slabs. The first 5cm of the snow was pencil hard, then the next 10cm was 4F. Below the top 15cm the snow was 1F to the ground and rightside up, with no gross basal facets. This slope must not have had snow prior to the storm. 

We did a column test and got fractures in both windslabs, CTE 9 for the first one at 5cm and CTM12 in the lower one fracturing at 15cm, with clean breaks on both. We then did an ECT test and again got the two windslab layers breaking very easily, but with no propogation. Paired with stomping on our switchbacks and only getting broken plates coming off, we were not worried about anything more than some little chunks of crust being loosened.

I did not notice any whumphing in the lower, sheltered west facing trees today. 

 

Any other comments about the observation or links to outside pages that have more info on the observation: 

Despite the wind board and crusty-ness the riding was really good today! There were patches of snow without a wind crust and they were great! I was able to ride a rib down a good chunk of the gully and make nice powder turns with little to no crust and without hitting rocks. The snow inbetween the soft stuff was wind board, but not bad. Down low in the trees the snow is fantastic and by looking ahead and being careful you can have a ton of fun and not hit any rocks. 

Weather Observations
Blowing Snow: 
Yes
Cloud Cover: 
25% of the sky covered by clouds
Air temperature: 
Below Freezing
Wind Speed: 
Strong
Precipitation: 
None
Air temperature trend: 
Cooling
Wind Direction: 
South
More detailed information about the weather: 

It was quite windy today, with loads of spindrift. The wind was all over the place in our gully, sometimes blowing upslope, sometimes blowing downslope. Across the South Lake drainage however, there was a massive amount of snow being blown by a southerly (maybe south easterly, not too sure beyond southerly) wind. There were huge plumes blowing off of all the major peaks... except for the one we were on:) Gilbert especially had an insane plume, and I would not want to ride any of the steep north facing couloirs in the area. It was also quite cold up high, my water bottle froze in my backpack.

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