January 16, 2021
January 17, 2021
Zone or Region:
Sawtooth Mountains - East of Chelan
Did you observe any avalanches? Yes
Size 3: Could bury and destroy a car, damage a truck, destroy a wood frame house, or break a few trees
East aspect near treeline. 33deg slope. 7300'. Started (probably during last ppt event a few days prior) as a likely shallow (20cm), small (7m wide) wind slab, ran a short distance, and stepped down (>80cm) and propagated widely (>50m) across the slope. Picked up some wet loose character as it moved downslope. Slide ran >1000' to valley bottom.
Did you see shooting cracks? Yes, Isolated
Did you experience collapsing or whumpfing? Yes, Isolated
Nearby pit (same slope) revealed HS 205cm with multiple weak layers terminating with 55cm of faceted depth hoar above ground. No early December crust observed. CT3 @ 10cm (SP Q2), CT6 @ 20cm, CT16 @ 70cm. These three layers failed on similar SH (looking) crystals (2-4mm). Several other large crowns observed on N to E aspects in area. Recent wind deposited snow was reactive but not deep. Snowpack (and likely danger level) at this location appears significantly different from what is being reported for/elsewhere in the North East Zone.