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NNMAE Snow Pack Report

SF ski area - 1/20/10

Submitted by: Bob

Location: snow study area
Date: Jan 20, 2010 Temp (C): -11
Wind Speed: 20 Wind Direction: NW

Dug a pit in the ski area at about 11,300 ft between Benny's Cliff and lower First Tracks.

Snow depth: 85 cm, slope 39 degrees, snowing

40-85 cm dry new snow, fist resistance
15-40 cm - dry solid faceted crystals, 1 mm, fist resistance
10-15 cm - dry solid faceted crystals, 1-2 mm, fist resistance
15 cm - dry ice masses & 5-7 mm crystals, pencil resistance
10-15 cm - dry solid faceted crystals, sugary, 2-3 mm, fist resistance
0-5 cm - dry solid faceted crystals 3-5mm, sugary, fist resistance

Shear test - easy, q2 bed at 15 cm
Compression test - 16, collapse at 15 cm
Reutschblock test - 2, collapse and shear when weighted by skier.

So it's still fairly unstable a day after the storm. It raises concerns about similar slopes steeper than 30 degrees that haven't been skier compacted.

I heard from a Big T skier that said yesterday his party was walking 20-30 feet from the edge of the ridge leading into the watershed and they were setting off avalanches on the east facing slopes. Whoomphing and shooting cracks, oh my!