Deep!

Location Name: Flathead Range Observation date: Friday, April 3, 2020 - 20:15	Is this an Avalanche Observation: No

Observation made by: Public

Tabs

Quick Observation

We chose a low-angle ridge to avoid the stress of the Persistent Slab problem.

Settled snow depths above last weekends rain crust: 9" at 4500', 14" at 4500', 17" at 5000' and 22"+ above 6000'. Most of this snow is low-density.
Our pit on a NE aspect at 6900' revealed a Persistent Slab snowpack structure that was obvious to the naked eye. Our party felt 2 collapses in the snowpack above 5500' associated with this problem. More info under the snowpack tab.
Light to moderate SW winds transported snow above 6000' and formed fresh soft cornices that broke under the weight of a skier. We traveled on wind-affected snow but no slabs found due to avoiding wind loaded terrain.
Near freezing temperatures on the valley floor resulted in warm sticky snow in the late afternoon with snow above 4500' remaining light and fluffy.

Snowpack, Avalanche, Weather Images:

Travel Details

Region:

Flathead Range - Middle Fork Corridor

Activity:

Skiing

Snowpack Details

Snowpack and Weather Details:

Terrain

Elevation of observation:

3500-5000 ft

5000-6500 ft

Above 6500 ft

Aspect(s) of observation:

N

NE

E

Red Flags:

More than a foot of new snow or heavy snowfall rates (>1"/hr)

Blowing snow

Persistent Weak Layers:

Not observed

New Snow in the past 24 hours:

6.00in.

More comments about the snowpack and weather:

Persistent slab structure consisted of 2" of weak faceted snow beneath 20" of snow at 6900'. We had a failure with a clean shear in a compression test with moderate force CT 15. No propagation with our one ECT.

Blowing Snow:

Light

Wind Speed:

Moderate (Small trees sway)

Wind Direction:

Southwest

Snow line:

valley floor

Sky Cover:

Partly Cloudy (SCT)

Highest Precipitation Rate:

Very Light Snowfall (S-1)