|Location:||Magnum NW shoulder|
Route & General Observations
We skinned up the the West facing meadows below Magnum to the NW ridge at 2750′. No obvious signs of instability were observed. Dug in several locations to look at the reactivity of facet on top of the mid January crust in the mid elevation band.
Skies were obscured, but around 2pm a few patches of clear skies appeared
Winds were calm during our tour, but ridge top winds did pick up from the West later in the afternoon. Seattle Wx recorded an average of 18 mph and gust to 44mph at 4pm.
3" new snow by 1:30pm at all elevations
Dug several pits at two elevations just off the NW ridge where there was a more consolidated upside down slab. The ridge route was pretty scoured with 10-30cm of m/f crust and sastrugi. For the most part we were able to stay off the slab while ascending.
Location 1) see video - 2050', NW aspect, 25* slope - Height of snow varied from 130cm to 170cm between three pits sites. We all had failure and propagation on well developed facets (2mm) on a stout curst about 35cm (14") below the surface. Slab density ranged from 1F hard to 4F. Test results: ECTP10, ECPT12, ECTP19, ECTP20, ECTN19x2, ECTN11, ECTN13
Location 2) 2750', NW aspect, 30* slope, Height of snow varied from 130cm to 200cm. All three pits were within 20' of each other. The Jan. 21 buried surface hoar layer (mixed with facets) was found in all three pit locations about 30cm below the surface. Slab densities ranged from 1F to Pencil hard snow. Only one pit location had propagation. Test results: ECTP19, ECTP20 (RP) slab was solid pencil hard and dropped out of pit. Test results in the the other two pits were ECTX, ECTN16, ECTN19, ECTN21 - slab was brittle and broke under shovel. The mid January crust was about 50cm below the surface and there were no notable test results on this layer.