THIS AVALANCHE ADVISORY EXPIRED ON April 7, 2018 @ 6:57 am
Avalanche Advisory published on April 6, 2018 @ 6:57 am
Issued by Jeff Thompson - Idaho Panhandle Avalanche Center

Selkirks/Cabinets

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A strong weather system is currently moving through northern Idaho.  Today, expect to see strong winds, snow and freezing temperatures. Yesterday's rain/snow mix saturated the top 6-8'' of the snowpack and made it avalanche prone. Temperatures overnight were cold enough to lock it back up though. I'd expect to see a firm refrozen surface today with places of wind deposited snow on top.  I wouldn't expect to see any natural activity today but human triggered avalanches are possible.

How to read the advisory

Selkirks/Cabinets

How to read the advisory

A strong weather system is currently moving through northern Idaho.  Today, expect to see strong winds, snow and freezing temperatures. Yesterday's rain/snow mix saturated the top 6-8'' of the snowpack and made it avalanche prone. Temperatures overnight were cold enough to lock it back up though. I'd expect to see a firm refrozen surface today with places of wind deposited snow on top.  I wouldn't expect to see any natural activity today but human triggered avalanches are possible.

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: Loose Wet
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Looking at temperatures this morning, I think the greatest chance of triggering a slide would be on isolated terrain features near/below treeline, where temperatures stayed a little warmer. It looks like any terrain above 4500' got cold last night.  I don't see it being a wet slide issue until it warms up again.  Above treeline you want to be aware of newly wind deposited snow. Winds changed last night from SW to N so pockets of wind slab could be any aspect. Hollow sounding or squeaky snow could be a sign that your on a wind slab.

Avalanche Problem 2: Deep Slab
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You're heard us talking about it all season and we're not going to stop now! Yesterdays rain/snow mix put another heavy load on the snowpack which increases avalanche danger. The snowpack doesn't like a lot of weight added in short amount of time. The avalanche danger associated with deep slab instability will decrease as the snowpack gets used to the newly added weight.  With that said, all of this snow has to head to the rivers some how! So...besides a new load on the snowpack, warm temperatures are the other red light when it comes to deep slab avalanche indicators. The further we push winter into spring, the more dramatic it will be when we do have a significant warm spell. 

Weather and CURRENT CONDITIONS
Weather observations from the Region
0600 temperature: 28 deg. F.
Max. temperature in the last 24 hours: 38 deg. F.
Average wind direction during the last 24 hours: SW
Average wind speed during the last 24 hours: 10-15 mph
Maximum wind gust in the last 24 hours: 39 mph
New snowfall in the last 24 hours: 6 inches
Total snow depth: 146 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 Chance of rain Rain
Temperatures: 43 deg. F. 35 deg. F. 46 deg. F.
Wind Direction: NE E SW
Wind Speed: 7-14 6-10 12-17
Expected snowfall: >.5'' in. 0 in. 0 in.
For 4000 ft. to 6000 ft.
Friday Friday Night Saturday
Weather: Snow showers Chance of snow Rain/snow
Temperatures: 33 deg. F. 32 deg. F. 38 deg. F.
Wind Direction: NE NE NE
Wind Speed: 14-24 9-15 18-24 G33
Expected snowfall: 1-2 in. 0-1 in. 1-3 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.

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