THIS AVALANCHE ADVISORY EXPIRED ON February 10, 2018 @ 6:58 am
Avalanche Advisory published on February 9, 2018 @ 6:58 am
Issued by Melissa Hendrickson - Idaho Panhandle Avalanche Center

St. Regis Basin/Silver Valley

bottom line

The forecast is back to winter-like temperatures, which will help lock up all the moisture we've been seeing in the pack this week and increase the stability.  Variable amounts of snow (1-5") fell across the forecast region last night, creating the potential for windslab formation. It is important as backcountry users that we evaluate the snow and terrain carefully to identify these areas.  

How to read the advisory

St. Regis Basin/Silver Valley

How to read the advisory

The forecast is back to winter-like temperatures, which will help lock up all the moisture we've been seeing in the pack this week and increase the stability.  Variable amounts of snow (1-5") fell across the forecast region last night, creating the potential for windslab formation. It is important as backcountry users that we evaluate the snow and terrain carefully to identify these areas.  

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: Wind Slab
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Variable amounts of new snow , as well as variable winds associated with the cold front have provided the potential for windslab formation. Use caution when traveling on windward slopes.  

Avalanche Problem 2: Persistent Slab
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Reports of persistent weak layers have been getting fewer and further isolated for our forecast area, but we can't let our guard down yet.  It is important to dig and assess each location to see if you find them. And please send me observations of where you do find them! 

recent observations

We travelled to Gold HIll yesterday and observed widespread wet loose slides and some wet slab slides. The warmer weather and rain that we've had the past week really heated up and destabilized the snowpack. We were able to easily trigger roller balls and wet loose slides in small terrain features.  The good news is that a cold front came in overnight and will lock all that moisture into place and increase the stability of the pack.  Temperatues look to be staying cold for a while, so the lower pack will be stabilizing.  It will be important to note how new snow coming in bonds to this surface as well as keep a heads up for surface hoar formation during the cool, clear nights we are forecasted for tonight and tomorrow.  

We have the Silver Mountain Backcountry Weekend coming up on Saturday and Sunday, details here.  Looks to be good weather, but come prepared for chillier temperatures than we've been experiencing lately.  All activities during the day are outdoors. And don't forget the Friends of IPAC fundraiser at the Coeur d'Alene Bike Co on Monday night, details here.  

And as usual, send in observations, we really appreciate them. 

Weather and CURRENT CONDITIONS
Weather observations from the Region
0600 temperature: 15 deg. F.
Max. temperature in the last 24 hours: 37 deg. F.
Average wind direction during the last 24 hours: NNW
Average wind speed during the last 24 hours: 8 mph
Maximum wind gust in the last 24 hours: 26 mph
New snowfall in the last 24 hours: 1-5" inches
Total snow depth: 61 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Spokane NWS
For 2000 ft. to 4000 ft.
Friday Friday Night Saturday
Weather: Mostly Sunny Mostly Clear Sunny
Temperatures: 32 deg. F. 17 deg. F. 31 deg. F.
Wind Direction: NE NE Variable to West
Wind Speed: 7-9 6-8 5-8
Expected snowfall: 0 in. 0 in. 0 in.
For 4000 ft. to 6000 ft.
Friday Friday Night Saturday
Weather: Chance Snow Showers Partly Cloudy Sunny
Temperatures: 17 and dropping deg. F. 11 deg. F. 18 deg. F.
Wind Direction: NE NE W
Wind Speed: 7-13 5-9 6-11
Expected snowfall: <0.5 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.