THIS AVALANCHE ADVISORY EXPIRED ON March 31, 2018 @ 6:39 am
Avalanche Advisory published on March 30, 2018 @ 6:39 am
Issued by Kevin Davis - Idaho Panhandle Avalanche Center

Selkirks/Cabinets

bottom line

The mountains have not picked up an appreciable amount of new snow since last week and the mild weather has settled the pack nicely.  Diurnal temperatures are creating a breakable crust at the surface on all aspects.  The north aspect has some layers in last weeks snow but not too concerning.  Watch windloaded areas, mainly N and E, in steep terrain where windslabs could fail.

How to read the advisory

Selkirks/Cabinets

How to read the advisory

The mountains have not picked up an appreciable amount of new snow since last week and the mild weather has settled the pack nicely.  Diurnal temperatures are creating a breakable crust at the surface on all aspects.  The north aspect has some layers in last weeks snow but not too concerning.  Watch windloaded areas, mainly N and E, in steep terrain where windslabs could fail.

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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Windslabs are most pronounced on North through SE aspects.  Overall the pack is settling and trend toward stable conditions but in the isolated areas around ridgetops and under cornices youmay find windslabs that could be touchy enough to trigger in steep terrain.  Convex areas may be another feature to watch for unstable slabs.  We did find a couple crust layers that failed with moderate force on the sugar snow above.  It's not too likely that they will fail this weekend but triggering the windslab could create the force to trigger the deeper crust layers.  Something to be aware of when looking at consequences.  Overall, the sliding on the north aspect was great with good surface snow on a supportable base.

Avalanche Problem 2: Normal Caution
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There area  few layers in the pack identifiable on all aspects.  The upper pack and surface conditions are quite similar on all aspects too.  Settlement over the last week is creating more uniform conditions.  On north aspects the layers are more intact and still show angular grains which are weaker.  North aspects is where I would use the most caution.  With the weather expected for the weekend the concern about the deep weak layer from February 4th is not a concern.  It will come into play as spring conditions prevail and daytime temps get warm.

Avalanche Problem 3: Loose Wet
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Loose wet slides may be a problem on Saturday if the sun gets out from behind the clouds.  Nice problem to have, right?  With NE winds expected and sunshine be thinking that SW and W aspects could be getting on the warm side later in the day so be thinking about where you might be as the temperature begins to soften those aspects.  If its turning to deep slush you shouldn't be there, especially steep terrain.

recent observations

No recent observations of avalanche activity in the past week.  What I noticed in our travels in the Selkirks yesterday was that the sliding conditions are good right now and should stay that way with the expected weather.  The wind should keep the pack firmed up even if the sun peeks out Saturday but watch for the change in wind direction.  Late afternoon westerly asepcts could heat up enough on Saturday.  Lower elevation snow in protected areas seems to be effected the most by daytime warming and could get a little rotten during the heat of the day.  Get it while it's good but don't push it if you haven't paid attention to the stability and considered the consequences.  Summer is right around the corner.

Weather and CURRENT CONDITIONS
weather summary
Today through Sunday...Good agreement exists between the latest
models in maintaining a general northwesterly flow aloft over the
region through the next few days. Two weak transient disturbances
of note will slide by...one this morning which will promote heavy
morning clouds and a chance of valley rain and mountain snow
showers through this evening mainly concentrated over the
northeast Washington mountain zones and the Idaho panhandle...due
mainly to orographic forcing. The general flow regime will allow
a few showers over these regions saturday as well...while the
basin benefits from downslope drying in this flow regime. A
second and possibly stronger short wave will approach the region
on Sunday and allow another relative higher pop period...once
again concentrated over the northeast mountains and Idaho
panhandle.
Weather observations from the Region
0600 temperature: 31 deg. F.
Max. temperature in the last 24 hours: 37 deg. F.
Average wind direction during the last 24 hours: West
Average wind speed during the last 24 hours: 25 mph
Maximum wind gust in the last 24 hours: 49 mph
New snowfall in the last 24 hours: 0.0 inches
Total snow depth: 155 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.  For a recorded version of the Avalanche Advisory call (208)765-7323.