Bollettino valanghe

Selkirk Mountains

Idaho Panhandle Avalanche Center
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Pericolo valanghe

Wed
Alta quota
1 · Debole
Limite del bosco
1 · Debole
Sotto il limite
1 · Debole
Non aggiornato — questo bollettino è scaduto 5 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Solar input and warm temperatures continue to drive changes in the snowpack. Today, expect to see wide variability in conditions on different aspects and elevations. Generally safe avalanche conditions exist. However, wind loaded slopes and steep slopes above treeline are still the most likely place to find unstable snow which increases the risk of avalanche in those areas.

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Unlikely
    Dimensione
    1–1.5

    Wind slabs and cornices continue to grow on Leeward slopes near ridgelines. Be aware of SE-E-NE facing slopes above treeline and below ridges

    Windward slope above Roman Nose Lake 

    North facing, 6400'

  • Loose Wet

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–2

    Be aware of warm temperatures and sunshine on the snow. Sun effected snow can lose stability the longer it's effected by sunshine. 

Avalanche Discussion

Yesterday, we visited the Roman Nose area in the Selkirks. Even though there was enough snow at the trailhead, it was very noticeable how fast the snow is melting. We experienced soft, sun-affected snow from the valley floor all the way to 4900’. On the snowmobile ride up, there were places on the road that were melting, and we could hear water moving underneath us. The lower elevation snow is helping keep the watershed percentages close to normal. If we continue to see melting in the valleys, the snow percentages will begin to drop quickly. Let’s hope we see that valley snow stick around for a while longer or we could see a quick onset of spring conditions in the mountains.

Once we got up to the Ruby Saddle (5400’) on the sleds, the conditions felt much more like winter. The quick blast of snow we got yesterday arrived while we were at Roman Nose Lake bringing three inches of new snow in that quick moving storm. We observed light snow transport by the southwest wind. The cornice formation and wind loading on the slopes above Roman Nose Lake were noticeable and increasing as we dug our snow pit.

There are two crust layers in the upper portion of the snowpack. The deeper crust is a rain crust from early January which is easy to find on all aspects at upper elevations. In most places, this crust has 4-8’’ of snow on top of it. The snow has been blown off on windward slopes where this crust is on the surface. The second crust layer is a recent sun crust found primarily on south and east facing slopes. Under both crusts are weak facets. Below the crust layers, the snow is strong and supportable all the way to the ground.

Travel conditions are favorable right now. The snowpack is supportable, which allowed us to take the sleds off trail and go exploring.  Snow on low angle, north facing slopes near treeline proved to be the best riding conditions. Be aware of changing and varying conditions on different aspects and elevations. Have a great day!

 

Regioni coperte