Southern Sierra - Snow conditions, warming

SNOWPACK OBSERVATION Mt.Williamson area Lone Pine
Submission Info Forecaster Saturday, March 11, 2017 - 11:00am

Contributor

Josh Feinberg

Red Flags:

36° 39' 24.048" N, 118° 18' 39.2724" W

See map: Google Maps

Snowpit Observations

More detailed information about the snowpack:

-Snowline on Northfacing slopes down to 6,400'. All the forest service dirt roads are clear for the trailheads in the WIlliamson area.

-We observed no signs of instability anywhere ... that being said we were above 11,000' from morning until late afternoon.

-SE facing Slopes above 13,000' at noon = ski pen~3cm, boot pen~5cm. Shallow surface moistening and softening. See attached photo.

-S facing slopes between 11,000 and 12,000' near rocky cliffs at 3:30pm were soft and moist and in places would sink to knee.

-No signs of any loose-wet point releases at all on southerly slopes above 11,000' by mid to late afternoon.

-Below 9,000' south facing slopes were isothermal and by late afternoon were fairly unsupportable for boot packing.

-Above 9,000' heavy wind effect almost everywhere at all aspects with very firm wind-board and sastrugi. By late afternoon northerly facing slopes were moist and thick up to 9000'.

*Looking at things positively, there was no breakable crust in the alpine! But virtualy no soft snow except for varying degrees of solar softening on slopes with alteast a little southerly aspect and were time dependent. Again, greatest hazards were firm conditions, and at lower elevations late in the day, mank.

Snowpack photos:

Weather Observations

Blowing Snow:

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More detailed information about the weather:

Clear sunny day with increasing high clouds in the mid-morning and afternoon. Calm winds throughout except for some light northerly gusts over ridgetops. Very pleasant sitting in the sun at 13,000' at 11am. Warm!