Bollettino valanghe

East Cabinet Mountains

Idaho Panhandle Avalanche Center
Vedi sulla mappa

Pericolo valanghe

Sat
Alta quota
2 · Moderato
Limite del bosco
2 · Moderato
Sotto il limite
2 · Moderato
Non aggiornato — questo bollettino è scaduto 6 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

2021 Already! Starting the new year off with some thin storm slabs that will continue to build in thickness through Sunday. Much of this new snow is resting on a layer of buried surface hoar below treeline (Roughly 6,500'). These slabs may be reactive and thin until Saturday. Saturday night a fresh round of heavy snow will cause avalanche danger to rise significantly by Sunday morning.

Problemi valanghivi

  • Storm Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely
    Dimensione
    1

    The East and West Cabinets have picked up 6-8" of fresh snow since Wednesday morning. This new snow may be resting on a bed of surface hoar below 6,500'. This will create a poor surface for bonding and may cause the new storm snow to slide easily. These storm slabs may be relatively harmless through Friday but will become thicker, more cohesive and more dangerous as new storms roll through the area later in the weekend. By late Saturday and Sunday the avalanche danger will likely rise to Considerable.

     

    Photo of magnum sized surface hoar crystals on December 28th in East Cabinets.

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    2–3

    We still have a deep persistent weak layer lurking out there. This layer consists of a firm base layer that dates back to November, resting on this firm base is a layer of weak sugary snow.  The depth and sensitivity of this layer varies with aspect, elevation and mountain range; but, it is safe to say it is wide spread. Triggering this layer will be possible at upper elevations in steep terrain that is unsupported and poorly anchored. It is low on the likelihood scale but very dangerous if triggered. The Upper elevations of the Purcell Range and East Cabinets is where I would use particular caution. Check out the video below to see what we are dealing with.

     

Avalanche Discussion

Here's what I saw out there on New Years Eve. Steady and modest snowfall has graced the Cabinets with a new and softer surface, the Purcells didn't seem to pick up much snow which is often par for the course. During todays tour I was on high alert looking for buried surface hoar, it's tricky business, hard to say where it was growing and surviving before it was buried. The best guidance I can give is to assume it may be there below 6,500', especially in open timber and steep creek draws. Pay attention to cracking in the snow surface and utilize small test slopes or high banks for clues.

The more predictable part of this game is the weather forecast, at this point the Weather Service is predicting a pretty good wolloping of snow starting Saturday evening. This rapid loading of new snow will elevate the avalanche danger on Sunday, time to dial it back and stick to lower angle terrain on Sunday.

Regioni coperte