Public Observation #2021-476
Submitted:December 13, 2021 6:06 PM
Observation Date:December 13, 2021
Zone or Region:Central Cascades
Did you trigger any avalanches?Yes
Was it intentional?Yes
Avalanche Type:Dry Loose (sluff)
Size:D1: Relatively harmless to people
Comments:While skiing down W/NW side (~6500ft) a purposeful hard cut turn on a small isolated higher angle section of terrain (maybe about 40 degree angle estimate) caused a roughly 7-inch deep fracture and about 15 foot wide chunk to break loose and slide roughly 10 feet down.
Signs of Unstable Snow
ObservationsDid a lap on Tumalo today. Got to summit around 2pm - Whiteout conditions, extremely low visibility at times, high winds with strong gusts from south. Coverage was good.
Dug a pit and did a column test on Tumalo bowl east facing slope. Pit was at top of bowl (~7776 elev), but on a slightly lesser angled slope on top for safety - keep results in mind, given this was a mild angled test and not the actual slope angle of the bowl. East and Northern slopes were heavily wind loaded as the forecast today mentioned. Pit results on a single column test dug to dirt showed propagation at CT12 at 70cm and CT13 at 65CM. Total depth was 90cm. No additional propagation beyond that, the snow base seems to be bonding decently well. But that still leaves roughly a foot of snow that did break with the slap from the elbow, definitely worth being aware of - but didn't seem too surprising with current storm and new snow levels.
Watched 1 other guy do some turns down the bowl, then I went. No incidents.
Later, while skiing down W/NW side (~6500ft) a purposeful hard cut turn on a isolated higher angle section did cause a roughly 7-inch deep fracture and about 15 foot wide chunk to slide a about 7 feet down. This makes sense, given results of isolated column test.
Took some photos of conditions and small pit results, site isn't allowing me to add right now, but the important stuff is all written above.