THIS AVALANCHE ADVISORY EXPIRED ON March 4, 2017 @ 11:32 am
Avalanche Advisory published on March 3, 2017 @ 11:32 am
Issued by Eric Morgan - Idaho Panhandle Avalanche Center

Selkirks/Cabinets
St. Regis Basin/Silver Valley

bottom line

In the Bitteroots near Lookout Pass we have 3 feet recent storm snow which has a decent bond to the 8 inch icecrust from 3 weeks ago with some instability within the top 3 feet of storm snow due minor snow density changes between these storms.  Things are starting to consolidate.  The upper few inches of snow have some wind affect in most areas with more on steep exposed upper elevations.  

How to read the advisory


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

Selkirks/Cabinets
St. Regis Basin/Silver Valley

How to read the advisory

2. Moderate

?

Above Treeline

2. Moderate

?

Near Treeline

2. Moderate

?

Below Treeline

In the Bitteroots near Lookout Pass we have 3 feet recent storm snow which has a decent bond to the 8 inch icecrust from 3 weeks ago with some instability within the top 3 feet of storm snow due minor snow density changes between these storms.  Things are starting to consolidate.  The upper few inches of snow have some wind affect in most areas with more on steep exposed upper elevations.  

  • 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

Watch for cornice failures in wind affected areas.  Exposed areas will have more wind slab buildup than sheltered areas.  

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

With up to 1-2 feet coming this weekend, this will be a rapid change to the upper snowpack which is low density.  The incoming snow will be much warmer than that of this week and will therefore be heavy on light.  This will take a few days for the lighter snow to accept the heavier snow.  

recent observations

3 feet of storm snow from this week, large cornice build up on ridgetops sitting on an ice bridge.  

CURRENT CONDITIONS Weather observations from the Region
0600 temperature: 29 deg. F.
Max. temperature in the last 24 hours: 32 deg. F.
Average wind direction during the last 24 hours: 240
Average wind speed during the last 24 hours: 10 mph
Maximum wind gust in the last 24 hours: 25 mph
New snowfall in the last 24 hours: 6 inches
Total snow depth: 120 inches
weather

Expect continuous snow with up to 2 feet through the weekend.  Temperatures above freezing today, continually getting cooler through the weekend with night temperatures in the low 20's.  Winds SW 10-15 G25.  

Disclaimer

This avalanche advisory is provided through a partnership between the Idaho Panhandle National Forest and Friends of IPAC. This advisory covers the Bitteroot Mountains in the Idaho Panhandle. This advisory applies only to backcountry areas outside established ski area boundaries. This advisory describes general avalanche conditions and local variations always occur. This advisory expires 24 hours after the posted time unless otherwise noted. The information in this advisory is provided by the USDA Forest Service who is solely responsible for its content.

For a recorded version of the Avalanche Advisory call (530) 587-3558 x258