Bollettino valanghe

Seeley Lake

West Central Montana Avalanche Center
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Pericolo valanghe

Wed
Alta quota
3 · Marcato
Limite del bosco
3 · Marcato
Sotto il limite
3 · Marcato
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In sintesi

Today, continued snowfall, sustained winds, and rising temperatures impact the area and build storm slabs across all elevations and aspects. The weight of a human or machine is likely to trigger avalanches in steep terrain, and medium to large-sized natural avalanches are possible. Use a ski pole, probe, or small hand pits to feel for stronger over weak snow as you travel. Look to avoid slopes steeper than 30 degrees in areas with stronger over weak snow or if you find shooting cracks or collapsing nearby. 

Problemi valanghivi

  • Storm Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely
    Dimensione
    1–2.5

    Fresh snow and rising temperatures leave us with danger from storm slab avalanches at all elevations. While the new snow yesterday was of low density and lacked the cohesion needed for destructive slab avalanches in most areas, touchy wind-hardened storm slabs were observed in the Seeley Lake zone.   Changing temperatures will change the recipe, leading to more touchy storm slabs, especially where winds are in the mix. Expect the heavier snow and winds to mix and consolidate with the 4 to 10 inches from yesterday into medium to large-sized storm slabs today.  

    Tilt tests, ski cut results on small, inconsequential slopes or natural activity on indicator slopes are often the best clues that a storm slab problem exists. Look for shooting cracks or collapses. If you see these, stick to slopes 30 degrees or less and put a large terrain buffer between you and avalanche-prone slopes. 

    (1/31/2022)

    Example storm slab and shooting cracks from the Seeley Lake zone.

    Photo: Trask Baughman 

Avalanche Discussion

Temperatures dropped to the mid-teens yesterday as a cold storm arrived. Before that, cold nights, clear skies, inversions, and warm days were the picture. Yesterday's snow totals are in the 4 to 10-inch range, with the northern reaches of the area favored. Winds were moderate to strong out of the west-northwest. 

After a long dry spell, it's refreshing to see fresh snow, but it's best to remember that the forecast area hosts variable snow structures. Some are weak. Clear, cool conditions sucked moisture from the snowpack. Near-surface facets and various surface hoar layers exist. Sheltered areas are the most likely to harbor persistent grains. Today, we're leaving persistent off the problem list as storm snow is the main driver. However, avalanches may run larger or on less steep slopes than expected if they step down to or trigger on these buried weak layers. 

Ridgetop winds have stayed in the moderate to strong range throughout the storm. Wind directions have shifted around the compass, with the west winning out as the dominant direction. Expect a switch to a more easterly flow this afternoon.

Temperatures are expected to moderate into the upper teens to low twenties today then cool below zero °F tonight. Keep an eye out for loose dry avalanches. These sluffs could run easily in steep terrain. Observations reported up to 10 inches of dry loose snow yesterday. If it stays colder than forecasted, loose dry avalanches could become more of a problem.

Ski and ride safe

Regioni coperte