Rain Crust and Surface Hoar, Minaret Vista

Submission Info
Friday, January 5, 2018 - 9:45pm
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Recent loading by new snow, wind, or rain
37° 39' 6.4368" N, 119° 3' 16.2108" W
Snowpit Observations
More detailed information about the snowpack: 

Quick tour up to Minaret Summit confirmed other observations in the Mammoth area today: Yesterday's storm left little in the way of new snow, but a thin (1cm thick) breakable rain crust now covers the surface facets that had previously been our top snow layer. 1-2mm surface hoar (see photo) was widespread on top of the rain crust except on southerly aspects where crusts were already melting and becoming moist. With the warm temperatures again today I suspect much of the surface hoar will degrade prior to the next storm, especially if it comes in warm and with some wind. But sheltered areas will be places to watch before Monday to see if the little ice feathers are still around before they get buried by new snow.

Field weather observation at 0945 at 9,000' on an open SE aspect: Sky= Overcast (but sun visible, OVC-); Wind= light from the WNW, occasional gusts to moderate; Tair= 4C, Tsurf= -0.5C, T-20= -1.5C; Surface= 2mm surface hoar on top of 1cm thick rain crust; Ski pen= 0cm, Boot pen= 20cm (RNcr too hard break through just standing on skis, but boot broke through easily and sank deep into the near surface facets underneath).

Skiing was lousy breakable crust rain crust.

Snowpack photos: 
1-2mm surface hoard on 1cm thick rain crust.
Weather Observations
Blowing Snow: 
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More detailed information about the weather: 
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