Observations from Round Top

Location Name: 
Roundtop
Region: 
Carson Pass Area
Date and time of observation: 
Sun, 04/09/2017 - 12:00
Location Map: 
United States
38° 39' 44.7516" N, 120° 0' 13.4928" W
US


Red Flags: 
Recent loading by new snow, wind, or rain
Rapid warming
Obvious avalanche path

Observation made by: Professional Observer
Snowpit Observations
More detailed information about the snowpack: 

Cool SW wind in the Roundtop area today, that kept snow surfaces from transitioning to wet. We saw a few very small Dry Loose avalanches on E aspects that likely initiated when the morning sun first warmed the rocks at their initiation points. One similar but larger ~D2 was observed on South Bowl of Tallac from our drive through Meyers. 2 previous Wind Slab crowns were observed on very steep NE aspects of Deadwood Peak.

Pic 1: Wind filling in the skin track near the Roundtop/Sisters saddle. The skier ahead was just a few minutes in front of me. "Tiger striping" was evident on many slopes in this area, and snow was much denser than observed elsewhere yesterday.  However, no signs of current Wind Slab instabilities were observed today.

Pic 2: On the Summit City side of Roundtop, shallow snow on top of recent rain crust (now firm) was a concern, so we avoided steep slopes with this combo. Gullies with deeper new snow did not show signs of instabilities. Even by mid afternoon, the surface snow on the sunny Summit City side remained dry, and no signs of wet instabilities were observed.

The rocks on the summit of Roundtop had both rime ice and water ice from the recent rain. We attempted to reach our original objective via the summer trail through the rocks to the summit, but turned around due to the ice. Ice remained on the summit rocks when we passed back through the Roundtop/Sisters saddle later in the day, and likely didn't melt after our departure. If anyone plans to ski something from the summit of Roundtop before the next storm, consider booting up your line instead of using the summer trail.

Snowpack photos: 
Weather Observations
Blowing Snow: 
Yes
Cloud Cover: 
Clear
Air temperature: 
Below Freezing
Wind Speed: 
Moderate
Precipitation: 
None
Air temperature trend: 
Warming
Wind Direction: 
Southwest
Accumulation rate: 
None
More detailed information about the weather: 

Temps well above freezing at the bottom of Summit City, but below freezing near ridgetop and on the Hwy 88 side of Roundtop.