THIS AVALANCHE ADVISORY EXPIRED ON January 5, 2019 @ 6:22 am
Avalanche Advisory published on January 4, 2019 @ 6:22 am
Issued by Eric Morgan - Idaho Panhandle Avalanche Center

Selkirks/Cabinets

bottom line

Heavy snow and high winds will create wind and storm slabs on a dense snow pack with increasing avalanche hazard.  The overall hazard rating is considerable for the Selkirk and Cabinets.  

How to read the advisory

Selkirks/Cabinets

How to read the advisory

Heavy snow and high winds will create wind and storm slabs on a dense snow pack with increasing avalanche hazard.  The overall hazard rating is considerable for the Selkirk and Cabinets.  

3. Considerable

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

2. Moderate

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

1. Low

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Below Treeline
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
    Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential.
Avalanche Problem 1: Wind Slab
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Expect deep windslabs on leeward slopes that will be easy to trigger on steep open slopes in the upper elevations. 

Avalanche Problem 2: Storm Slab
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Recent storm snow will take some time to settle to old snow.  Watch for these slabs on steep and convex rollovers.

Avalanche Problem 3: Persistent Slab
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There has been some observations of persistent weak layers although nothing popped out to us yesterday, but this is something that is variable across the forecast area.  It has been about a 3 feet deepwith some facets and a layer with some surface hoar.

advisory discussion

In the Selkirks yesterday Kevin and I found windy conditions with 4 inches of fresh that was reactive on old surface snow.  Windloaded aspects had 18 plus inch windslabs that presumably grew overnight.  Temperatures were increasing at the end of the day to the point where it was freezing rain/rain at 5000 feet.  Things are likely to be on the heavy side which will potentially make things unstable until settling occurs.  Big exposed steep windloaded terrain will be the stuff to avoid this weekend with the quick changes in wind, precipitation, and temperatures hanging at the 32 mark.  

recent observations

Yesterday we saw snow accumulations with increasing temperatures at the end of the day.  As the day went on there were numerous cracks due to a fresh and weak bond on the older snow.  There was a weakness a foot below the surface where older storms interfaced.  We did not find any persistent weak layers within the pack but this is something that has been previously observed and should be thought of in big terrain.

Weather and CURRENT CONDITIONS
weather summary

Snow with breezy conditions picking up to 4 inches today with another 4 through Saturday night.  Winds will decreasing to 10-15 until Sunday where more will come with increasing precipitation again.  Temperatures will be high of 31 and low 22.

Weather observations from the Region
0600 temperature: 28 deg. F.
Max. temperature in the last 24 hours: 31 deg. F.
Average wind direction during the last 24 hours: 200
Average wind speed during the last 24 hours: 23 mph
Maximum wind gust in the last 24 hours: 32 mph
New snowfall in the last 24 hours: 4 inches
Total snow depth: 63 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Spokane NWS
For 2000 ft. to 4000 ft.
Friday Friday Night Saturday
Weather: Rain...snow rain
Temperatures: 37 deg. F. deg. F. deg. F.
Wind Direction: South
Wind Speed: 5-7
Expected snowfall: 0 in. in. in.
For 4000 ft. to 6000 ft.
Friday Friday Night Saturday
Weather: Snow 2-4 1/2 1/2
Temperatures: 30 deg. F. 22 deg. F. 31 deg. F.
Wind Direction:
Wind Speed:
Expected snowfall: in. in. 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.