Mammoth Crest Near Blue Crag

Submission Info
Monday, February 12, 2018 - 1:00pm
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Recent loading by new snow, wind, or rain
37° 34' 8.4" N, 118° 58' 45.84" W
Snowpit Observations
More detailed information about the snowpack: 

Toured up the Sky Meadows Trail from Coldwater Campground to the saddle between Sky Meadows and Barney Lakes, right under Blue Crag. Was tracking precipitation type, rate, and duration, as well as new snow depths and winds. Also wanted to dig and look at how quickly the cold temps were affecting the strength of the faceted snowpack on N aspects near treeline.

Showers were moderate off and on with precipitation rate ranging from very light to moderate (S-1 to S2) throughout the day. Winds were suprisingly light and no blowing snow was visible, snow was staying up in tree branches. New snow was between 5 and 10cm depending on tree cover (less under trees). There were occasional breaks between showers when the sky opened up for a few patchs of blue (BKN) but overall the day was overcast and cold. Air temp was -8.5 deg C at 1120am. Conditions on S and E aspects, and N and W aspects below 10,000', were dust on crust. Above ~10,000' N aspects were softer faceted snow under about 10cm of new snow (skied like boot top powder).

Profile dug on a N facing aspect at 10,128' just above Sky Meadows near treeline (see attached profile). The snowpack is largely faceted except the remains of melt-freeze crusts from earlier this season. Temperature gradient was again at threshold to drive faceting until very near the ground. Test results showed potential for fracture initiation in facet layers near buried crusts, but no propensity for propagation. Probing above and below my profile site on N aspects showed that the snow structure found in my pit was about the same everywhere that the snow depth was similar, ~1m. I had some very local cracking above treeline right as I got to the saddle, both in the new snow which by this point had a very slight density change with very slightly heavier snow at the surface (all new snow was cold, dry, and F- hard), and in places that the most recent melt-freeze crust was breakable. Ski cuts on rollovers on the way down had no results. No signs of wind transport or new avalanches on the Crest, but visibility was only occasionally good enough to see it.

Don't be fooled by a few inches of new snow covering over the tops of obstacles! There is still patchy and very shallow snow below ~9500' (see photo). There is getting to be almost no snow on the roads in the Lakes Basin. Today I walked all the way up to the Coldwater Campground turn off. What Tamarack has been grooming is mostly a few inches of sheet ice under the new snow. Caution and a good ski tuner are advised.

Snowpit or crown profile photo or graph: 
Snowpack photos: 
Don't let a few inches fool you, still poor coverage up to 9500'
Weather Observations
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