THIS AVALANCHE ADVISORY EXPIRED ON March 11, 2017 @ 7:20 am
Avalanche Advisory published on March 10, 2017 @ 7:20 am
Issued by Eric Morgan - Idaho Panhandle Avalanche Center

St. Regis Basin/Silver Valley

bottom line

Melissa and MIiles found about 110cm of new snow since the rain 3 weeks ago. So far, it has all landed right side up and settling. Snowfall yesterday was already beginning to get denser as they were headed out.  Concerns are windslabs in the N-NE-E aspects near and above treeline and the recent storm slabs.  

How to read the advisory


  • Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.

St. Regis Basin/Silver Valley

How to read the advisory

2. Moderate

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Above Treeline

2. Moderate

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Near Treeline

2. Moderate

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Below Treeline

Melissa and MIiles found about 110cm of new snow since the rain 3 weeks ago. So far, it has all landed right side up and settling. Snowfall yesterday was already beginning to get denser as they were headed out.  Concerns are windslabs in the N-NE-E aspects near and above treeline and the recent storm slabs.  

  • Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
Avalanche Problem 1: Wind Slab
  • Character ?
  • Aspect/Elevation ?
  • Likelihood ?
    Certain
    Very Likely
    Likely
    Possible
    Unlikely
  • Size ?
    Historic
    Very Large
    Large
    Small

Wind slabs will be your biggest concern today and you'll find these on easterly aspects above 5,000 feet.  Wind transport may slow down as the temperatures continue to rise but wind-loading has already built up deep and unstable pockets that will possibly get more so with the very warm temperatures and rain.  Steep lee aspects should be avoided today.

Avalanche Problem 2: Storm Slab
  • Character ?
  • Aspect/Elevation ?
  • Likelihood ?
    Certain
    Very Likely
    Likely
    Possible
    Unlikely
  • Size ?
    Historic
    Very Large
    Large
    Small

Although we are starting to see some rapid settlement due to snow loading and warming you should be suspect of lingering instability in the new snow we have received in the past week.  Melissa found a right-side-up pack but layers popped out so these will be tested with the warming and likelihood of rain.  Lookout Pass is reporting 4 inches of new in the last 24 hours and 32 inches in the last 48 hours.  Give the pack some time to settle before you venture into avalanche terrain.

CURRENT CONDITIONS Weather observations from the Region
0600 temperature: 38 deg. F.
Max. temperature in the last 24 hours: 38 deg. F.
Average wind direction during the last 24 hours: W
Average wind speed during the last 24 hours: 20 mph
Maximum wind gust in the last 24 hours: 26 mph
New snowfall in the last 24 hours: 4 inches
Total snow depth: 108 inches
Disclaimer

Avalanche conditions change for better or worse continually. Backcountry travelers should be prepared to assess current conditions for themselves, plan their routes of travel accordingly, and never travel alone. Backcountry travelers can reduce their exposure to avalanche hazards by utilizing timbered trails and ridge routes and by avoiding open and exposed terrain with slope angles of 30 degrees or more. Backcountry travelers should carry the necessary avalanche rescue equipment such as a shovel, avalanche probe or probe ski poles, a rescue beacon and a well-equipped first aid kit.  For a recorded version of the Avalanche Advisory call (208)765-7323.