THIS AVALANCHE ADVISORY EXPIRED ON February 9, 2019 @ 6:11 am
Avalanche Advisory published on February 8, 2019 @ 6:11 am
Issued by Kevin Davis - Idaho Panhandle Avalanche Center

Selkirks/Cabinets

bottom line

Watch windloaded ridgelines that could exist on multiple aspects today, now under a little more snow load.  We saw some natural windslab avalanches on windloaded ridges yesterday on Gunsight and Monday near Trestle Peak.  It snowed all night!  Temperatures are in the single digits up high so the new snow is light.  More snow with extreme cold expected today.  Avalanche danger will increase this weekend due to strong NE winds.

How to read the advisory

Selkirks/Cabinets

How to read the advisory

Watch windloaded ridgelines that could exist on multiple aspects today, now under a little more snow load.  We saw some natural windslab avalanches on windloaded ridges yesterday on Gunsight and Monday near Trestle Peak.  It snowed all night!  Temperatures are in the single digits up high so the new snow is light.  More snow with extreme cold expected today.  Avalanche danger will increase this weekend due to strong NE winds.

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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I'm mentioning a storm slab just to describe the new snow conditions.  Eric and I found the surface new snow from this week to be consitently very light and about 6 inches deep on all aspects.  The snow is too light to create a cohesive slab that could create an avalanche.  It looks like the Selkirks and Cabinets got 6 more inches of champagne powder last night so the conditions should be superb if you can tough the cold.  Loose snow sloughs will be your main concern in the foot of surface snow today before the wind gets to it.

Avalanche Problem 2: Wind Slab
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Like I said, we've seen windslab avalanches a couple times this week just below ridgelines.  These slabs are built up on multiple aspects due to shifting winds.  The slabs were shallow but now there is more snow on top.  Yesterday windloading was occurring as the west wind picked up.  The touchy areas will be easy to identify as the open and loaded areas just under cornices or ridgelines on any aspect steeper than 30 degrees.

Avalanche Problem 3: Persistent Slab
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We did not find the buried surface hoar layer that we've been tracking yesterday around Gunsight Peak in the Selkirks.  We looked hard for it on multiple aspects and in likely areas I was surprised not to find it.  Doesn't mean its not there.  It just means that you have to know where to be on your A game when you find yourself venturing into those likely areas which are, sheltered NW through SE aspects.  It'll most likely be down off the ridgetops a few hundred vertical feet in openings in the trees or protected faces above sheltered drainages.  Watch steep slopes in that type of terrain.  The type of terrain where you feel like you're protected out of the weather and you have some smaller yet challenging terrain to play on with good snow, yeah that stuff.  Check it first.  The nasty layer is less than two feet down with corn flakes so you'll see it easily.

advisory discussion

It's backcountry weekend at Silver Mountain this weekend!  Get up there to practice with folks from Panhandle Backcountry and IPAC to hone your avalanche skills.  They'll be taking people on tours to Warnder Peak, digging pits, assessing terrain, practicing beacon searches, and more.  This is a great opportunity to get out and learn from the folks that spend their time working and playing in the mountains.  Don't forget too that the Doug Abromeit Avalanche Scholarship has been extended to the end of this month.  If you're between the ages of 14 and 24 all you need to do is write an essay and you could win a free level 1 avalanche class with IPAC!  Look for details on the IPAC education page.

Weather and CURRENT CONDITIONS
weather summary

The big thing you'll notice today in the mountains is the super light powder.  About 6 inches has fallen in the Cabinet and Selkirks.  Then the cold will get your attention.  Mountain temps this morning vary from 8-12 degrees.  Winds are westerly in the 5-10mph range.  Some snow will be blowing and drifting.  As a Noreaster blows in tonight the winds will pick up and the temps will drop further.  More snow expected for the next few days as the Noreaster blasts the region with extreme cold, NE winds, and more snow.  Avalanche conditions will increase mainly due to windloaded snow.

Weather observations from the Region
0600 temperature: 8 deg. F.
Max. temperature in the last 24 hours: 10 deg. F.
Average wind direction during the last 24 hours: NW
Average wind speed during the last 24 hours: 8 mph
Maximum wind gust in the last 24 hours: 10 mph
New snowfall in the last 24 hours: 6 inches
Total snow depth: 85 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Spokane NWS
For 2000 ft. to 4000 ft.
Friday Friday Night Saturday
Weather: Snow. Chance of precipitation is 80%. Snow, mainly before 10pm. Chance of precipitation is 90%. A 50 percent chance of snow.
Temperatures: 25 deg. F. 4 deg. F. 12 deg. F.
Wind Direction: N NE NE
Wind Speed: 6mph 14-24mph with gusts to 33 28-30 with gusts to 48
Expected snowfall: 1 in. 1 in. <1/2 in.
For 4000 ft. to 6000 ft.
Friday Friday Night Saturday
Weather: Snow, mainly after 7am. Wind chill values as low as -3. Chance of precipitation is 80%. Snow. Wind chill values as low as -31. Chance of precipitation is 90%. Snow likely, mainly before 4pm. Widespread blowing snow. Mostly cloudy and cold, with a high near 4. Wind chill values as low as -35. Very windy, with a northeast wind 36 to 39 mph, with gusts as high as 65 mph. Chance of precipitation is 60%. New snow accumulation of less than one inch possible.
Temperatures: 13 deg. F. -5 deg. F. 4 deg. F.
Wind Direction: W turning E NE NE
Wind Speed: 6mph 16-26mph increasing to 27-37 36-39 with gusts to 65
Expected snowfall: 1-2 in. 1-3 in. <1 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.