Route & General Observations
Found the Martin Luther King day (MLK) buried surface hoar (BSH) in three areas in an East bowl of Raggedtop between 2400′ and 2900′. Tests were mostly unreactive and didn’t propagate. Talked with a group who skied in this zone yesterday and triggered two small slabs (D1’s) without incident. The light was really flat, but we could see tracks and two very small crowns between 3500′ ad 3800′ on an East aspect.
Obvious signs of instability
|Recent Avalanches?||Yes||Collapsing (Whumphing)?||No||Cracking (Shooting cracks)?||No|
Two small D1 slabs on an East facing gully
Wet loose point releases on South aspect of Goat - likely from yesterday or day before when sun was out.
Overcast and valley fog rolled in around 3pm
Temps were in the upper 20F's to low 30F's.
1000' 1500'- Needle like surface hoar on 3-5" loose settle snow (near surface facets) sitting on supportable crust
1700' - 2900' a low density 8mm rime crust with 2-3mm surface hoar on top on soft settle snow. A firm crust under the loose settle snow could be felt with poles to around 2000.'
HS at 1700' was 100cm.
Dug several pits at 2400' and found the Martin Luther King Day buried surface hoar 'MLK BSH' down 45-50cm in three pits. This layer was sitting on a 1cm pencil hard melt-freeze crust. The snow above this layer was pencil hard. Extended Column Tests didn't show propagation propensity. (ECTX x 3, ECTN30, PST 95/110 End, CT25, CTN) HS=145cm. The surface hoar was stuck to the melt/freeze below. Some of the BSH grains were 6-sided with slight cup shapes on some. See photos below.
Dug two more quick pits. One in a shallow area (HS=80cm) on SE aspect off of a sub ridge at 2800'. MLK BSH was down 15cm, but CT's failed with moderate force on 4F hard facets 30cm below surface. Slab was 1F to 4F.
Another quick pit at 2900' in a more loaded spot the MLK BSH was ~50cm below the surface, CT21 on BSH. The grains were more feather-like and were on a thin MF crust on Pencil hard snow. Slab was P to 1F hard.