Bollettino valanghe

Silver Valley & Bitterroot Mountains

Idaho Panhandle Avalanche Center
Vedi sulla mappa

Pericolo valanghe

Wed
Alta quota
1 · Debole
Limite del bosco
1 · Debole
Sotto il limite
1 · Debole
Open full map
Non aggiornato — questo bollettino è scaduto 4 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Generally stable snowpack conditions are present across the zone. A layer of buried surface is present in isolated locations at treeline and above in locations sheltered from the wind. This layer is not proving to be reactive in stability tests at this time; however, it is wise to stop and dig a pit to check for the presence and reactivity of buried surface hoar at your location.

Problemi valanghivi

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Unlikely
    Dimensione
    1.5–2.5

    During yesterday's tour in St. Regis Basin we found a layer of surface hoar buried in sheltered terrain at the upper edge of treeline. We found this layer on a north-westerly aspect and east facing terrain. This layer is not showing a likelihood to propagate and is bridged by our 2" thick "Lucky Friday Crust". Observations from the past week have not been finding buried surface hoar, which leads me to believe it is unlikely to be widely distributed across the area. The challenge with surface hoar is mapping where it grew and stayed intact prior to being buried. Buried surface hoar is often highly variable in reactivity once buried. The take home message here is that despite a generally stable snowpack and a low likelihood of triggering avalanches today, it is always wise to take the time to dig into the snow and see what is under your feet before committing to steep and consequential terrain.

Avalanche Discussion

On Monday, Issy Davis and I took a quick tour outside the boundaries of Lookout Pass to the St. Regis basin area. (Big thanks to Lookout Pass Ski Area for the free lift ride!) We took a hard look at the snow on both sides of the ridge at the upper end of Treeline before dropping into the basin to do a hasty pit at lower elevations. Finding the layer of buried surface hoar was surprising considering it hasn't been present in pits at prior locations the past two weeks.  Our current snowpack stability is such that triggering an avalanche is unlikely; however, I would still continue to be cautious and do your homework before jumping into big terrain. The other thing that I have my eye on is the upper crust layer and the weak faceted snow that is developing above and below it. It is not a concern right now as we still lack a cohesive slab above it. If we get a storm slab on top of our current surface, it will bond poorly and cause a problem that may last awhile.

 

Regioni coperte