THIS AVALANCHE ADVISORY EXPIRED ON April 3, 2019 @ 4:46 am
Avalanche Advisory published on April 2, 2019 @ 4:46 am
Issued by Ben Bernall - Kootenai National Forest

Kootenai

bottom line

Avalanche danger will continue to be driven by the sun on Tuesday. Expect to find firm surfaces and LOW avalanche danger in the mornings followed by the potential for small, loose-wet slides to develop in the afternoon on steep, rocky terrain that is exposed to the sun on south and west aspects. Continue to pay attention to objective hazards above you such as Glide Cracks and Cornices that may be getting weak in the sun.

How to read the advisory

Avalanche danger will continue to be driven by the sun on Tuesday. Expect to find firm surfaces and LOW avalanche danger in the mornings followed by the potential for small, loose-wet slides to develop in the afternoon on steep, rocky terrain that is exposed to the sun on south and west aspects. Continue to pay attention to objective hazards above you such as Glide Cracks and Cornices that may be getting weak in the sun.

1. Low

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Above Treeline
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

1. Low

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Near Treeline
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

1. Low

?

Below Treeline
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
    Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
Avalanche Problem 1: Loose Wet
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Loose wet slides will continue to be the main avalanche concern on Tuesday as the sun comes out and heats the surface of the snow pack. With freezing night time temperatures the snowpack will lock together at night and reduce both the size and frequency of these slides with each daily freeze/thaw cycle. The most likely spots to encounter this problem will be in steep terrain with rocky outcroppings that are exposed to the sun. South and west aspects with thin snowpack are the most likely trouble spots at this time.

Avalanche Problem 2: Glide
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Glide cracks continue to be seen on most any aspect or elevation where the continuous warm temperatures have caused free water to lubricate the underlying bed surface, this problem may be a concern where the snow is resting on rock slab or bear grass. We have yet to see any slides associated with this problem and with the cold nights it is a very low likelihood issue; but, it is a potential. If we return to a weather pattern where we encounter multiple days above freezing the potential for this problem will rise, particularly on aspects exposed to the sun. Watch for large cracks on steep slopes and avoid lingering under these features on warm or sunny days. Super simple.



Don't stand under the frowns.


 

advisory discussion

On Monday we toured into the East Cabinets via the "Bull RIver Side". We found firm conditions on all aspects with a very thin skim of fresh snow still lingering at the upper elevations. All the avalanche activity we viewed was older and we saw nothing new release yesterday. Most of the older avalanche debris we did view was pretty well limited to south and west aspects particularly on slopes that are getting very thin in coverage. These areas had released on the ground (last week or weekend likely) and formed small "loose-wet slides" at all elevations we viewed yesterday. These are the areas where you may see small slides this week when the sun pokes out. As far as the more "objective hazards" lurking out there we viewed a couple spots where cornices had broken off at and there are still glide cracks open at multiple aspects and elevations. With the snotel sites showing a return to freezing temps each night we are unlikely to see much activity out of these issues; but, it is always wise to pay attention to the little things when travelling in the mountains. 

Weather and CURRENT CONDITIONS
weather summary
Backcountry Forecast from NWS Missoula issued:
340 AM MDT Tue Apr 2 2019

DISCUSSION: A pleasant day is expected for western Montana today,
with a mix of sun and clouds. A light northeast breeze is again 
forecast for areas along the Continental Divide. Widespread 
valley rain and mountain snow showers is forecast for the day 
Wednesday, with an increase in southwesterly winds. Periods of a 
rain/snow mix is possible down to the valley floors along the 
divide late Wednesday evening and overnight. Little if any 
accumulations are expected.


Kootenai:

--------------------------- 5000-7000 FT ----------------------------
                      Today        Tonight      Wed      
Cloud Cover           20%          30%          90%      
Hi/Lo Temps           41 to 52     26 to 30     36 to 48 
Winds(mph)            NE  8G20     E  9G20      S  9G24  
Precip Chc            0            0            60       
Precip Type           none         none         showers  
Liquid Amt            0.00         0.00         0.16     
Snow Ratio(SLR)       0            0            11:1     
Snow Amt(in)          0            0            1-3      

Snow Level            4000         4000         4500 
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.