THIS AVALANCHE ADVISORY EXPIRED ON January 23, 2019 @ 6:06 am
Avalanche Advisory published on January 22, 2019 @ 6:06 am
Issued by Kevin Davis - Idaho Panhandle Avalanche Center

Selkirks/Cabinets

bottom line

You'll notice a "crust cake" in the upper two feet of snowpack with light snow in between each crust.  Some weak layers still exist in the light snow which has not fully settled due to the cold weather.  Be cautious in steep, convex terrain where you could trigger these upper weak layers today.  Winter Storm Warning issued tonight!

How to read the advisory

Selkirks/Cabinets

How to read the advisory

You'll notice a "crust cake" in the upper two feet of snowpack with light snow in between each crust.  Some weak layers still exist in the light snow which has not fully settled due to the cold weather.  Be cautious in steep, convex terrain where you could trigger these upper weak layers today.  Winter Storm Warning issued tonight!

2. Moderate

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

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.
    Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
Avalanche Problem 1: Storm Slab
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Storm snow from last week is still not completely settled but it is sealed between tow layers of crust.  Some weak layers exist in this unsettled portion of snow.  Triggering these weak layers is not a huge concern since the crusts are hleping to hold them in place but a small slide is possible that could take you for a ride.  The most likely place for this to happen is a steep, convex rollover on any aspect.  

Avalanche Problem 2: Persistent Slab
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It's getting less likely that you would trigger the persistent slab of surface hoar or faceted snow closer to the base but due to our relatively shallow snowpack and cold temperatures within the pack we need to mention that it is a mild concern.  Just like a bear attack while you're walking through the woods to a mountain lake; not likely to happen but you should be aware of the threat and how to avoid.   Cold northerly aspects on steep, exposed terrain are the places you're looking out for.  Triggering an upper weak layer would be a more likely scenario to trigger the persistent slab.

recent observations

No observations of avalanche activity in the recent past.  Conditions yesterday were crusty, on all aspects.  Very light new snow had fallen on the upper breakable crust.  This layering will be a concern for the storm that is forecast to hit our region tonight.  If you are planning on going to the mountains mid-week pay very close attention to the bond of new snow to the light snow over the crust.  Be cautious of windloaded slopes.  Look for the red flags; windloading, heavy new snow, rising temps, shooting cracks, avalanches.

Weather and CURRENT CONDITIONS
weather summary

The weather service forecast for today reads, "Snow, mainly after 7am. High near 25. Wind chill values as low as zero. Windy, with a southwest wind 22 to 25 mph. Chance of precipitation is 80%. New snow accumulation of 2 to 4 inches possible".  Cold new snow will create a weak contact over the upper crust.  Heavy new snow tonight will mostl likely create very hazardous avalanche conditions by Wednesday.  Be very cautious on all aspects if you are giong to the mountains.

Weather observations from the Region
0600 temperature: 20F deg. F.
Max. temperature in the last 24 hours: 24F deg. F.
Average wind direction during the last 24 hours: NW
Average wind speed during the last 24 hours: calm mph
Maximum wind gust in the last 24 hours: 8 mph
New snowfall in the last 24 hours: 0 inches
Total snow depth: 72 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Spokane NWS
For 2000 ft. to 4000 ft.
Tuesday Tuesday Night Wednesday
Weather: Snow likely, mainly after 10am. Chance of precipitation is 60%. Snow. The snow could be heavy at times. Chance of precipitation is 90%. Rain and snow before 7am, then snow between 7am and 9am, then rain after 9am. Chance of precipitation is 90%.
Temperatures: 34 deg. F. 31 deg. F. 38 deg. F.
Wind Direction: SW S SW
Wind Speed: 3-7, gusts to 18 6 3-6, gusts to 18
Expected snowfall: 2-4 in. 4-8 in. 1-2 in.
For 4000 ft. to 6000 ft.
Tuesday Tuesday Night Wednesday
Weather: Snow, mainly after 7am. High near 25. Chance of precipitation is 80%. Snow. The snow could be heavy at times. Chance of precipitation is 100%. Snow. The snow could be heavy at times. High near 31. Breezy, with a southwest wind 13 to 23 mph, with gusts as high as 36 mph. Chance of precipitation is 90%. New snow accumulation of 3 to 5 inches possible.
Temperatures: 25 deg. F. 26 deg. F. 31 deg. F.
Wind Direction: SW SW SW
Wind Speed: 22-25 18-23, gusts to 37 13-23, gusts to 36
Expected snowfall: 2-4 in. 7-11 in. 3-5 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.