Sluffing and no slab concerns yet in Rescue Creek

Location Name: Forecaster Observation - Rescue Creek, Flathead Range Observation date: Saturday, December 16, 2017 - 13:00	Is this an Avalanche Observation: Yes

Observation made by: Forecaster

Location

Tabs

Quick Observation

Not enough new snow or wind transport to form any new slabs over the weak 12/15 interface. No signs of cracking or slab instability
Skier triggered several loose avalanches that ran up to 1,000 feet on N and E aspects running on the Thanksgiving rain crust

Snowpack, Avalanche, Weather Images:

Travel Details

Region:

Flathead Range - Middle Fork Corridor

Route Description:

Rescue Creek trail to northerly and easterly slopes of Nyack Mountain and Mt. Penrose, up to an elevation of 7,700 ft.

Snowpack Details

Snowpack and Weather Details:

Terrain

Elevation of observation:

5000-6500 ft

Above 6500 ft

Aspect(s) of observation:

Persistent Weak Layers:

Buried

New Snow in the past 24 hours:

2.00in.

More comments about the snowpack and weather:

1-2" of new snow with very little wind transport. The new snow accumulated over the well-documented 12/15 interface (NSF/SH on northerly aspects, MFcr over FC on southerly aspects). Sluff management on northerly/easterly aspects was our only concern today, with up to 12" of fist hard, faceted snow over the Thanksgiving rain crust. Tested numerous leeward start zones but there was no sign of fresh wind slab formation in the areas that we traveled.

Avalanche Details

Avalanche Details:

Date and Time of Avalanche:

Saturday, December 16, 2017 - 13:00

Avalanche Type:

Loose Dry/ Sluff

Failure Plane/Weak Layer:

Old snow

More information or comments about the avalanche:

Several "facet sluffs" on N and E aspects above 6,000 ft.

Trigger

Trigger:

skier

Trigger Modifier:

Intentionally Triggered

Terrain

Start Zone Slope Angle:

Aspect:

Northeast

Starting Elevation:

above-treeline

Size

Destructive Size:

D1 Relatively harmless to people.

Relative Size:

R1 Very Small

Crown Height:

Less than 1 ft

Avalanche Length (Vertical Run):

800ft.

People Involved

Number of people caught:

Avalanche Location:

Date and Time of Avalanche:

Wednesday, November 22, 2017 - 21:30

Avalanche Type:

Unknown

Failure Plane/Weak Layer:

Unknown

More information or comments about the avalanche:

A number of old wet debris piles from the Thanksgiving cycle, up to D2.5 in size, originating on various NW to E aspects on Penrose and Nyack.

Trigger

Trigger:

natural

Terrain

Starting Elevation:

above-treeline

Size

Destructive Size:

D2 Could bury, injure, or kill a person.

Avalanche Location:

Avalanche Forecasts

Tutorials

Observations

Weather

Classes and Events

Videos

Online Resources

Friends of the Flathead Avalanche Center

Flathead Avalanche Center

Sluffing and no slab concerns yet in Rescue Creek

Location

Tabs

Call

Contact

In Partnership With

In Partnership With

Avalanche Forecasts

Tutorials

Observations

Weather

Classes and Events

Videos

Online Resources

Friends of the Flathead Avalanche Center

Flathead Avalanche Center

Sluffing and no slab concerns yet in Rescue Creek

Location

Tabs

Search

Follow or Subscribe

Call

Contact

In Partnership With

In Partnership With