Quick report
- Cracking
- widespread
A notably stormy and reactive day. Deep recent and new snow. Consistent, heavy snowfall with a slow warming trend. Widespread cracking and small triggered and natural storm slab avalanches by mid-afternoon.
Starting at 1:30p, shallow cracking and avalanches became widespread at middle and lower elevations. Long cracks were at least 30ft in length and could be seen in low-angle terrain (20deg), often adjacent to slopes that had slid.Weather
- Air Temp
- 30
- Cloud Cover
- obscured
- Wind Loading
- previous
- Rain Elevation
- 3500
- Recent Snowfall
- 35
- Snow Avail For Transport
- large amounts
Heavy snowfall all day from S2-S5 (1-2"/hr). At 9a, there was HN12 of 30cm. Very little wind. Slight warming trend, while precipitation remained all snow. We didn't measure accumulation when we exited the field at 3p, but it was increasing rapidly.
Snowpack
Most notable was the heavy, ongoing snowfall, creating "upside-down," hard-over-soft layering that resulted in widespread avalanches by mid-afternoon.
At 9 a.m., we found 30cm of new snow from the past 15 hours. On southerly slopes, this sat on the 3/10 crust, which was 1-2cm, frozen, and up to P+ hard.
Profile
Heather Ridge, NE, 5320ft
Snowing S2-5, currently calm but previously leeward (3/8-9)
HS 325cm, HN12 30cm, HST since 3/8: 95cm
0-3cm: Cohesive new snow currently falling
↓30cm: 3/10 interface, CTE (PC) on DFs
91-95cm: FC, 0.5-1mm, very sharp and angular, 3/8 melt-layer FC
95-96cm: crust, frozen, 3/8 crust
124-139cm: Moist melt forms and crusts, remnants of the mid-February crust/weak layers
139-150cm: Weak (4-Finger), moist, melt forms
See graph
Avalanche
- Size
- D1 R1
- Type
- SS
- Count
- 2
- Aspect
- E
- Trigger
- N
- Elevation
- 4600 ft
Extremely notable instability with small avalanches almost certain on slopes >35 degrees. Starting around 1:30p, widespread triggered and natural storm slab avalanches from 5-10cm, quickly gaining depth as warm snowfall accumulated. In one run from 5,150-4,960ft, we triggered at least 15 avalanches and saw another 5-10 naturals that were less than 1 hour old. All small, dry, D1 storm slabs. We triggered numerous avalanches remotely from above, below, and adjacent slopes. Some crowns wrapped around features, nearly 180 degrees, and connected features with multiple crowns spanning over 100ft.