THIS AVALANCHE ADVISORY EXPIRED ON February 26, 2020 @ 6:34 am
Avalanche Advisory published on February 25, 2020 @ 6:34 am
Issued by Kevin Davis - Idaho Panhandle Avalanche Center

Kootenai
Selkirks/Cabinets

bottom line

Snowfall continued in the Cabinets yesterday and it amounted to about a foot of light powder in the last 24 hours as of yesterday afternoon.  Watch for windslabs at the ridges and be aware that the buried surface hoar layer we found in the Selkirks is buried about 18 inches deep on sheltered aspects.  Manage your terrain and you'll have great sliding.

How to read the advisory

Kootenai
Selkirks/Cabinets

How to read the advisory

Snowfall continued in the Cabinets yesterday and it amounted to about a foot of light powder in the last 24 hours as of yesterday afternoon.  Watch for windslabs at the ridges and be aware that the buried surface hoar layer we found in the Selkirks is buried about 18 inches deep on sheltered aspects.  Manage your terrain and you'll have great sliding.

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: Wind Slab
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Windslabs at the ridgelines will be touchy since the storm on MOnday night came in with some heavy winds.  Easterly aspects will be your main concern but be careful on slopes that bend around to the north and south.  Surface conditions out there are mostly powder so pay attention to firmer conditions and note your position on the slope.  Winds in the higher terrain of the East Cabinets may be creating more areas that are prone to windslab instability so pay attention if you're heading for the high country of the Cabinet Wilderness area.

Avalanche Problem 2: Persistent Slab
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This layer of buried surface hoar is becoming stubborn as it has been buried long enough that it is gaining strength.  It takes alot of force to pop it out but it is very intact and it pops out clean and that tells us it is still something to watch.  Where this layer could get you is on steep, convex terrain in open spaced trees, just the place where you might feel good about the stability.  This crop of surface hoar survived sun and wind and it is now isolated to these sheltered areas.  The steady accumulation of snow has stabilized it but it is now 18 inches deep and could be triggered in the right/wrong place.

advisory discussion

This is the last week to get your submissions in for the Doug Abromeit Avalanche Scholarship.  Send it in to me at my email at work, kevin.davis2@usda.gov, and be eligible to win a free level 1 avalanche class.  How cool is that?

recent observations
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Surface conditions are mainly powder but the depth of the powder over a crust varys with aspect.  South aspects have about 4-6 inches of soft snow over a breakable crust.  West aspects vary with exposure to wind and sun.  On a sheltered west aspect at 6,000 feet we found about one foot of light new snow over another foot of denser snow that sits on top of a very firm crust.  North and east aspects were about the same as the sheltered west.  You should be good to go if you stay on sheltered slopes but watch the steep, convex terrain.  

Weather and CURRENT CONDITIONS
weather summary 
The weather today will be seasonably cool with a mix of clouds
and sun. A weak weather disturbance will bring clouds and light
mountain snow to the Cascades and mountains of the Idaho Panhandle
on Wednesday. Temperatures on Friday will likely be well above
average with many areas climbing into the 50s. The arrival of a
frontal system on Saturday will push temperatures down closer to
average and bring increasing chances for rain and mountain snow.
Weather observations from the Region
0600 temperature: 20F deg. F.
Max. temperature in the last 24 hours: 25F deg. F.
Average wind direction during the last 24 hours: calm
Average wind speed during the last 24 hours: calm mph
Maximum wind gust in the last 24 hours: NA mph
New snowfall in the last 24 hours: 1 inches
Total snow depth: 108 inches
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.