Bollettino valanghe

North Rockies

Mar 29 – 30, 2022Avalanche Canada
Vedi sulla mappa
Archiviato · scaduto 5 years ago

Pericolo valanghe

Thu
Fri
Alta quota
2 · Moderato
Limite del bosco
2 · Moderato
Sotto il limite
2 · Moderato
Apri la mappa completa

In sintesi

Fresh wind slabs are expected to form throughout the day. These slabs will be most reactive where they overlie a slick crust.

Loose wet avalanches are possible at lower elevations if the surface remains wet and unconsolidated.

Problemi valanghivi

  • Wind Slabs

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

    Wind slabs may be found in wind-loaded terrain in the alpine and treeline, formed by snowfall and westerly winds. These wind slabs will be most reactive where they overlie a slick crust.  

  • Loose Wet

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

    A poor overnight crust recovery followed by above freezing temperatures and rain at lower elevations may cause wet loose avalanches out of steep terrain. Watch for wet and heavy surface conditions. 

Confidence

Moderate - Uncertainty is due to how quickly the snowpack will recover and gain strength.

Weather Forecast

TUESDAY NIGHT: Increasing cloud cover. 30-50 km/h southwest winds. Freezing level dropping to 1000 m.

WEDNESDAY: Snowing, 5 cm of accumulation. 25-50 km/h northwest winds. Freezing level around 1400 m.

THURSDAY: Cloudy with light snowfall, up to 5 cm accumulation. 30-50 km/h northwest winds. Freezing level around 1400 m.

FRIDAY: Cloudy with light flurries. 20-40 km/h southwest winds. Freezing level around 1300 m.

Avalanche Summary

On Monday, a size 1.5 skier-triggered wind slab occurred on south aspect at treeline. This wind slab failed on a slick crust below the new snow. 

Several small (size 1-1.5) wet loose avalanches were observed on Sunday and Monday at treeline and below. 

Snowpack Summary

5-10 cm of new snow overlies 20 cm of heavier snow that tapers rapidly with elevation. Westerly winds may have formed small pockets of windslab in the alpine and exposed treeline. A refrozen crust can be found below the new snow on all aspects as high as 2400 m. Below the crust, the top 10-30 cm of the snowpack is moist.

There are no deeper concerns at this time.

Terrain and Travel

  • When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.
  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Wind slabs may be poorly bonded to the underlying crust.
  • As surface loses cohesion due to melting, loose wet avalanches become common in steeper terrain.

Regioni coperte