Gaylor Peak: New Snow Stability

SNOWPACK OBSERVATION
Gaylor Peak
Submission Info
Forecaster
Wednesday, April 18, 2018 - 3:30pm
Red Flags: 
Recent loading by new snow, wind, or rain
Gaylor Peak 37° 55' 13.08" N, 119° 15' 56.16" W
Snowpit Observations
More detailed information about the snowpack: 

Snowpit 1

Observer: d lewis
Loc: Gaylor Peak
Lat/Lon:37.9203, -119.2656
Elevation: 10800 f
Aspect: NNW Angle: 25°
Signs of Instability: Wind Loading
Sky Cover: -BKN
Precipitation: No Precipitation
Wind Speed: Light, beaufort
Wind Direction: SW
Current Temp:-1.5°C Trend:
Blowing Snow: Light SW
New Snow Storm: 20cm 
Snow Temperature 20cm: -5.5° C 
Boot Penetration: 25cm 3 Stability Tests: CTN 0cm CT26 Q3 73cm CT22 Q3 48cm

Snowpit 2

Observer: d lewis
Loc: Gaylor Peak, NE
Lat/Lon:37.9225, -119.2613
Elevation: 10350 f
Aspect: NNW Angle: 25°
Sky Cover: BKN
Precipitation: No Precipitation
Wind Speed: Light, beaufort
Wind Direction: SW
Current Temp:0 to -5°C Trend:
Blowing Snow: Light
New Snow Storm: 20cm 
Boot Penetration: 25cm
Snow Stability: Good
Stability on similar slopes:Good
Avalanche Danger: Moderate 3 Stability Tests: CTN 0cm CT28 Q3 55cm Unable to duplicate CTN 0cm

Comments: Traveled up to Gaylor Peak just outside Yosemite NP to assess the new snow stability and general snowpack condition. The drive up the road from the gate showed more evidence of our March slide cycles with debris cleared from the road in numerous places. Ellery Lake Bowl was a bit rocky with numerous large boulders poking through the snowpack, this is likely due to a large slide in March or early April’s rain event. A large crown is still visible along the top of the bowl and extending toward “Chute Out”, debris at the bottom is still visible. Gaylor Peak snow coverage often exceeded 240 cm on probing. Multiple melt freeze crusts in the upper 2/3 of the snowpack has for the most part capped and secured the snowpack below ~ 10500’. Above 10,500’ on northerly aspects the snowpack is still cold and dry both at the surface down into the upper snowpack. On arrival 10 to 25 cm new snow overlaying a well-developed melt freeze crust. As the day progressed and warmed the high cloud cover was reradiating and warming the surface 10 to 15cm of new snow became moist below ~10100’ with some minor wet sluffing on steep convex rolls on N-NE aspects where the snow was disturbed. No new natural avalanche activity noted. 1 lone roller ball noted originating from a easterly facing rock feature near the summit. Stability test were inconclusive, failures were isolated and inconsistent, unable to duplicate. Air temperatures remained cool through the day but the surface snow was showing signs of warming by mid-day below ~10300’ on even N-NE aspects. Above 10300, all aspects but N-NE, supportive melt/freeze crust at the surface and transitioning to corn.       

 

Snowpit or crown profile photo or graph: 
Snowpack photos: 
Mt. Dana, West: Snow Coverage
Weather Observations
Blowing Snow: 
Yes
Cloud Cover: 
100% of the sky covered by clouds
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: 

Mid to high level cloud cover obscuring the sky except to the east. At times strong redaiation. Moderate ridgetop winds were producing light snow transport. Skin track ws partially filled in within a couple of hours. 

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