Observation type
Snowpack Observer greg Keep me anonymous if published no Location (general area) Baldy Bowl Date (yyyymmdd) 20130209 Time 12p Road conditions to area icy CF Temperature high 20s Sky clear (no clouds) Wind speed Light (1-16mph Flags/twigs in motion) Wind direction not observed Wind direction in degrees from NE in am, S in pm Slope aspect East Slope angle 30 Elevation 8200 Snow depth 75cm Boot/ Ski penetration 30cm Precipitation None Activity, recent avalanches No Brief description ECT16 propagated across entire ECT block - Q2 failure Whumphing noises, shooting cracks. collapsing no Rapid warming no Obvious avalanche path no Terrain trap no Comment Aspect: East. 8200 feet. Total snowpack depth: 75cm Top 10cm is fist hardness powder Next 20cm is two finger hardness powder Next is a 3cm layer of rain crust. Next is a 3cm layer of very low density hoar. Bottom 40cm is a cohesive, dense block going all the way to the ground. It appears the storm started off pretty warm and gradually cooled. The first snow over the old rain crust is quite dense and is well bonded. The powder is consolidating into a slab and is bonding pretty well to the rain crust. I was only able to get a Q3 very ragged failure at this boundary, but. . . Below the rain crust is a very poorly bonded hoar layer that failed my shear propagation test on ECT16 and propagated across the entire ECT block. The top 35cm slab slipped forward a centimeter on my 30 degree test slope and stopped. When I coaxed it it came off very cleanly with a very smooth but not rapid Q2 release. Despite the coldness of the storm, the new snow was slabbing up rapidly and I was easily able to lift chunks of the new snow off the rain crust below. I believe that once the new snow sets up into a cohesive slab tomorrow or the next day, we may have the potential for slab avalanches on E aspects at both the top and bottom of the 3cm rain crust. On a good note, the depth hoar at ground level is gone and the test block was well rooted to the dirt and rocks below. Other observations: Very icy roads in the morning. Snow dusted the mountains down to about 2500’. Extensive sloughing on steep couloirs at ~6500’. NW wind swept slopes all day today but snow was carried into the air and was not heavily deposited on lee slopes. New snow was very dry and squeaky under foot. Did not compact even along main trail. Lots of surface hoar on S facing slopes at 9am. Publish this observation Yes I would like this observation Published |