Snow conditions in the Mammoth Lakes Basin

Red Cone
Submission Info
Friday, January 31, 2020 - 2:30pm
Red Flags: 
37° 36' 4.878" N, 119° 1' 14.2608" W
Snowpit Observations
More detailed information about the snowpack: 

I ventured into the Mammoth lakes basin this afternoon hoping to evaluate the extent of surface warming. Particularly I was looking to see how today's warm ambient temperatures were affecting shaded northerly aspects. Unfortunately, My thermometer died today so I was not able to gather any temperatures of my own. Using the gauges on Mammoth mountain it looks like temps topped out around 2 pm with a high of 52° F at 9000’ and 49°F at 10000’. This seems to match up with my observations in the field. 

I traveled on easterly, northerly and northwesterly aspects today topping out at ~10000’ at around 3 pm. I observed the top 5-8 cm of the surface snow to be moist pretty much everywhere. No recent loose wet activity was observed but I noted lots of roller balls and pinwheels.  Isolated areas of natural rollers below cliff bands and rock outcroppings were a common sight and widespread rollerballs were initiated from my turns as I made way down the northerly trees to horseshoe lake. I made a point to kick on many steep rollovers and was able to initiate some very small soughing, but nothing substantial. 

I dug in on a NE aspect at 9300’ in the Red Cone trees and found a largely faceted but right-side-up snowpack. The most notable observation from my pit was that the rain crust from mid-December was almost entirely decomposed. (see profile for more details)

As I began my descent, I noticed immediately that the surface snow was sticky and heavy. This was exaggerated in thick trees where radiation was trapped under the tree cover. In more open areas that a thin zipper crust began to harden on the surface around 2:30 and travel was a bit quicker. As of 4 pm when I hit the car there had not yet been a hard refreeze.

My observations today indicated that solar aspects are a bit more cooked down while surface snow on more shaded northerly aspects is still relatively unconsolidated. Signs of instabilities related to warming were more prevalent in these shaded aspects at lower elevations. 

Snowpit or crown profile photo or graph: 
Snowpack photos: 
Weather Observations
Blowing Snow: 
Cloud Cover: 
100% of the sky covered by clouds
Air temperature: 
Above Freezing
Wind Speed: 
Air temperature trend: 
Wind Direction: 
Accumulation rate: 
More detailed information about the weather: 
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