Bollettino valanghe

West Slopes South

Northwest Avalanche Center
Vedi sulla mappa

Pericolo valanghe

Fri
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

You should continue to find generally safe avalanche conditions throughout much of the West South on Thursday. Keep an eye out for wind-drifted pockets or light and fluffy snow sliding quickly on the underlying firm surface. If you are on the volcanoes, expect to find deeper storm snow totals and potentially locally higher avalanche hazard.

Problemi valanghivi

  • Wind Slabs

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

    As you ascend in elevation, keep your eye out for freshly built Wind Slabs. These could exist throughout the zone, but are particularly of concern on the volcanoes where more precipitation fell during this storm. You can look for textured surfaces or fresh drifts behind objects as clues that the wind has been moving snow in the area you are traveling. If you notice smooth pillow-like piles of snow or stiff, hollow feeling snow under your feet, there’s a good chance you’ve found a Wind Slab to avoid. Any potential avalanche should be relatively small, but don’t get surprised by one in consequential terrain. Features such as steep unsupported slopes or convexities near terrain traps come to mind as areas that could have more serious consequences. 

    (3/9/2022)

    Drifting on the NW side of ridges above Panorama Pt. You can look for fresh drifts behind natural objects to help you identify wind-loaded areas.

    Photo: NPS Rainier Rangers

Avalanche Discussion

As is usually the case, the volcanoes outpaced the crest in this storm and ended up getting around 0.7” of water according to NWAC weather stations at Paradise and Mount St. Helens. Mount Rainier rangers reported anywhere from 4-8” of low-density new snow with larger wind drifts. These drifts are where you could run into trouble on Thursday, and may be isolated to the volcanoes. In the neighboring Snoqualmie Pass zone, we have good confirmation of hard Wind Slabs overlaying faceted snow on northerly slopes at upper elevations. We do not have any information about similar conditions in the West South, but take this into consideration during your travels and be leery if you notice a shady slope is wind-loaded.

Closer to the crest, 2-3” of new snow simply isn’t enough to drive much avalanche hazard after such a significant rain event last week hit the reset button on our snowpack. Still, you could have some small Dry Loose avalanches (sluffs) to manage. They could run far and fast on the underlying firm surfaces, so don’t get tripped up by one in an area where you don’t want to take a fall.

You could find that one of the bigger challenges is dealing with difficult travel conditions. A few inches of fresh snow certainly helped, but in most areas wasn’t enough to cover up the widespread avalanche debris, open creeks, rain runnels, or other variable surfaces the atmospheric river left behind. Allow yourself extra time to navigate these challenges and bring the right equipment if you are traveling on firm slopes to prevent a long and uncontrolled fall.

Regioni coperte