THIS AVALANCHE ADVISORY EXPIRED ON March 7, 2018 @ 6:57 am
Avalanche Advisory published on March 6, 2018 @ 6:57 am
Issued by Melissa Hendrickson - Idaho Panhandle Avalanche Center

St. Regis Basin/Silver Valley

bottom line

Small storms, light winds, and mild temperatures have helped stabilized the upper snowpack this week.  Caution is still needed in steep, high consequence terrain where loose dry avalanches are a possibility.  The persistent weak layer is still showing its face in some locations, so it is important that you check your location by digging down.  

How to read the advisory

St. Regis Basin/Silver Valley

How to read the advisory

Small storms, light winds, and mild temperatures have helped stabilized the upper snowpack this week.  Caution is still needed in steep, high consequence terrain where loose dry avalanches are a possibility.  The persistent weak layer is still showing its face in some locations, so it is important that you check your location by digging down.  

2. Moderate

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

1. Low

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Near Treeline
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

1. Low

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Below Treeline
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
    Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
Avalanche Problem 1: Loose Dry
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The low density snow blanketing our higher terrain is likely to create loose, dry sloughing in steeper terrain on all aspects. Remember that gloriously sunny day on Saturday?  This sloughing will be more problematic in the areas that got a healty dose of sun crust: the E-S-SW aspects.  

Avalanche Problem 2: Persistent Slab
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The persistent weak layer is buried under 3 ft of snow in most locations.  It's reaction in pit tests is varied spatially, so the only way you will know if it is in your location is to dig down.  Dig until you hit that rain crust about 3ft down and check out the layer at that interface.  

recent observations

I've been receiving lots of stellar observations this week, thank you to everyone who is helping us figure out where this persistent weak layer is. I had it react for me over the weekend in the Lone Lake Area, which was enough to make my party dial back our terrain choice.  It was not reacting for me at Eagle Peak, and reports from Silver Hill, Silver Mountain, and Glidden Ridge didn't have have it reacting in pit tests.   If you dig down when you are out, we'd love to hear from you.  Below are two examples of how people send observations, both are awesome! You can use our observation page or send me an email: mrhendrickson@fs.fed.us 

Weather and CURRENT CONDITIONS
weather summary

A warming trend is headed our way and with it comes a new set of avalanche problems.  This past Saturday was a glimpse at what will soon become the norm for temperatures for the rest of the winter (I can't guarantee the sunshine).  

Weather observations from the Region
0600 temperature: 26 deg. F.
Max. temperature in the last 24 hours: 28 deg. F.
Average wind direction during the last 24 hours: WNW
Average wind speed during the last 24 hours: 4 mph
Maximum wind gust in the last 24 hours: 16 mph
New snowfall in the last 24 hours: 1 inches
Total snow depth: 84 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Spokane NWS
For 2000 ft. to 4000 ft.
Tuesday Tuesday Night Wednesday
Weather: Slight chance snow showers then mostly sunny Partly Cloudy Mostly Sunny
Temperatures: 36 deg. F. 26 deg. F. 41 deg. F.
Wind Direction: SE E E
Wind Speed: 6 6 5-7
Expected snowfall: 0 in. 0 in. 0 in.
For 4000 ft. to 6000 ft.
Tuesday Tuesday Night Wednesday
Weather: Slight chance snow showers then partly sunny partly cloudy mostly sunny
Temperatures: 26 deg. F. 24 deg. F. 34 deg. F.
Wind Direction: SW SW S
Wind Speed: 6-8 8 8
Expected snowfall: 0 in. 0 in. 0 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.