THIS AVALANCHE ADVISORY EXPIRED ON January 11, 2020 @ 6:32 am
Avalanche Advisory published on January 10, 2020 @ 6:32 am
Issued by Melissa Hendrickson - Idaho Panhandle Avalanche Center

St. Regis Basin/Silver Valley

bottom line

The snowpack has started to settle, but this period will be brief. Another very large storm is hitting the region today, expect the avalanche danger to rise by Saturday morning.  Still expect to find storm slabs and wind slabs out there today.

How to read the advisory

St. Regis Basin/Silver Valley

How to read the advisory

The snowpack has started to settle, but this period will be brief. Another very large storm is hitting the region today, expect the avalanche danger to rise by Saturday morning.  Still expect to find storm slabs and wind slabs out there today.

3. Considerable

?

Above Treeline
Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential.

3. Considerable

?

Near Treeline
Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential.

2. Moderate

?

Below Treeline
Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
    Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential.
Avalanche Problem 1: Storm Slab
  • Type ?
  • Aspect/Elevation ?
  • Likelihood ?
    Certain
    Very Likely
    Likely
    Possible
    Unlikely
  • Size ?
    Historic
    Very Large
    Large
    Small

The snow from this week is settling and stabilizing, but it won't have a chance to get too comfy with the new snow coming in.  Friday - Saturday is supposed to deliver another 1 - 2 ft of snow at our higher elevations.  We are expecting significant snow at the lower elevations as well, so expect danger to rise across all elevation bands. There is a mixed surface for this snow to land on out there, some areas have a layer of graupel. This graupel (snow pellets/soft hail) is a poor bonding surface.  Red flags for storm slabs include shooting cracks.  If you see these in flat areas as you are approaching, stay out of the steeps.  Expect to avoid all avalanche terrain on Saturday.

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

The slabs from the last storm have started to strengthen but still possible to trigger by a rider. High winds coming from the S-SW for the next storm will create wind slabs on the N-NE aspects over the weekend.  Look for chalky, pillows of snow that sound hollow.  Red flags including cracking and whumphing. Plan to stay well clear of cornices and wind lips this weekend, or other likely wind slab areas in avalanche terrain.

Avalanche Problem 3: Deep Slab
  • Type ?
  • Aspect/Elevation ?
  • Likelihood ?
    Certain
    Very Likely
    Likely
    Possible
    Unlikely
  • Size ?
    Historic
    Very Large
    Large
    Small

The last storm cycle produced multiple avalanches that stepped down to this deep slab layer.  This was our persistent weak layers we've been talking about all season, but now they are buried more than a meter deep at most locations.  These are hard to predict as they are not reactive in pit tests, but keep in your mind that they are out there.  If they go, they will go big.  Dig down in your location to assess what you are dealing with.  

recent observations
Submit Snowpack Observations
Submit Avalanche Observations

Yesterday, the snow was starting to stabilize. We were seeing less reactivity in our pits, all the avalanche activity we observed was older, and we were only getting isolated cracking when traveling in moderate terrain.  This would be a great trend, except the weekend storm is throwing a wrench in that.  Expect danger conditions to rise as the new storm hits. There will be storm slabs at all elevations as the temperatures look to be holding below freezing and bringing us snow at the valley levels as well.  It will be a good weekend to stay conservative.  We will update the forecast if the conditions warrant an avalanche warning. 

Sorry about no video this week, we will be back to regularly scheduled Thursday videos next week. 

Weather and CURRENT CONDITIONS
Two-Day Mountain Weather Forecast Produced in partnership with the Spokane NWS
For 2000 ft. to 4000 ft.
Friday Friday Night Saturday
Weather: heavy snow heavy snow snow
Temperatures: 29 deg. F. 28 and rising deg. F. 34 deg. F.
Wind Direction: S S SW
Wind Speed: 6-9 10 9
Expected snowfall: 3-5 in. 4-8 in. 3-7 in.
For 4000 ft. to 6000 ft.
Friday Friday Night Saturday
Weather: Heavy snow and patchy blowing snow heavy snow and areas blowing snow heavy snow and patchy blowing snow
Temperatures: 22 deg. F. 21 and rising deg. F. 26 deg. F.
Wind Direction: S SW SW
Wind Speed: 14-24, G33 20-25, G36 13-15
Expected snowfall: 2-4 in. 5-9 in. 5-9 in.
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.