Blue Couloir, Mammoth Crest

SNOWPACK OBSERVATION
Submission Info
Forecaster
Monday, April 23, 2018 - 11:15am
Red Flags: 
Rapid warming
37° 33' 52.92" N, 118° 58' 51.24" W
Snowpit Observations
More detailed information about the snowpack: 

Toured up the Blue Couloir on the E end of the Mammoth Crest from the Tamarack cross country trails, back down the same way. Very warm with a poor refreeze overnight: Mammoth Pass reported nominally freezing temps for three hours last night, air temps today ranged from 8-10 deg C before 11am all the way up to 11,200'. Every aspect and elevation observed had transitiioned to spring corn snow except isolated wind slabs near the crest that formed from northerly winds on the 20th, which are well bonded now and have a stout melt-freeze crust on top with dry near surface facets below. All sun exposed areas below ~10,000' had softened to good corn with a supportable melt-freeze crust about 5cm below the surface by 1030am. Areas that were very sheltered were still frozen with a breakable 1F melt-freeze crust. Most snow above 10,000' was still frozen and P hard until about 1130am. E aspects and areas with open tree cover or near rocky areas thawed first, then S aspects and open slopes. Densely treed areas remained colder longer. Only very small rollerballs and wet sluffs from E facing test slopes at 10,000' around 1030am. Lots of evidence of recent rollerballs and D1 loose wet avalanches along the crest. The freshest evidence of wet instabilities was on northerly, higher elevation slopes which only warmed up recently.

Snowpack photos: 
Weather Observations
Blowing Snow: 
No
Cloud Cover: 
25% of the sky covered by clouds
Air temperature: 
Above Freezing
Wind Speed: 
Light
Precipitation: 
None
Air temperature trend: 
Warming
Wind Direction: 
Southwest
Accumulation rate: 
None
More detailed information about the weather: 

Occasionanly light SW breezes and clouds increasing from clear skies to scattered throughout today, and intense solar radiation under the high sun angle reflect a standard spring diurnal warming/cooling pattern. Rapid warming after warm overnight temperatures is increasing snowmelt and consolidation. Emerald lake and Cold water Creek are opening up.

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