Joshua Levigne and I snuck our way up to the top of Purple Bowl today via
Lipalian Pk's N ridge & summit (not exactly recommended but good fun). We
skied out via Wolverine Ridge. Ski quality ranged from excellent to
downright weird.
SNOWPACK: HS at TL is about 80 cm. In the alpine, 15-20 cm of low density
storm snow on top of a 15 cm 1F storm snow wind slab (from last night's wind
event) on top of about 40 cm of 1F to 4F facets, on top of 3 cm of F 8-10 mm
depth hoar.
AVALANCHE ACTIVITY: Strangely, until we crested Wolverine Ridge we observed
little cracking and no whoomfing. This all changed 100 m along the ridge
with a most extraordinary whoooommmmmpfmmpf lasting several seconds and
resounding across the ridge, sympathetically releasing, 15 m away, a size
1.5 slab that ran to ground down to the bottom of the bowl to the south
(2400 m).
Moments later, 500 meters away and on the opposite side of Purple Bowl (NE,
2400 m), a sz 2.0 slab sympathetically released, also to ground.
Further along Wolverine Ridge we propogated another sympathetic slab from 70
m away, this time on the N side of Wolverine Ridge and running to the bottom
of Wolverine Bowl, sz 2.5.
Also observed was a natural size 3.0 on from near the summit of Lipalian,
less than 24 hrs old.
Failure layer in all cases was depth hoar, about 8-10 mm, at the ground, 3
cm thick.
I would rate Danger:
Alpine: High
TL - Considerable
BTL - Low
We ended up at Purple bowl because the roads W and N were closed due to
avalanche control -- apparently Bosworth slid to the road, hitting some
cars. No injuries.
Regards,
Tom Wolfe
Ass't Alpine Guide
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