Bollettino valanghe

South Rockies

Jan 26 – 27, 2021Avalanche Canada
Vedi sulla mappa
Archiviato · scaduto 6 years ago

Pericolo valanghe

Thu
Fri
Alta quota
1 · Debole
Limite del bosco
1 · Debole
Sotto il limite
1 · Debole
Apri la mappa completa

In sintesi

There is little change right now with trace amounts of new snow and light winds. Nonetheless, keep in mind those classic Rockies hazards: shallow rocky snowpacks, stubborn hard wind slabs, cornices and variable wind-loading patterns.

Problemi valanghivi

  • Wind Slabs

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

    If winds pick up to moderate levels, snow may begin to form isolated wind slabs in the immediate lee of windy exposed ridge crests, in cross-loaded features or in steep alpine areas. Older hard wind slabs in the alpine linger, and while they are increasingly unlikely to trigger, they have the potential to propagate widely. Cornices continue to grow fragile with cold temperatures.  

Confidence

High - Confidence is due to a stable weather pattern with little change expected.

Weather Forecast

Another day of cloudy cool conditions before some forecasted light snow mid-week.

MONDAY NIGHT: Mainly cloudy with clear periods, light southwest wind, treeline temperatures around -12 C.

TUESDAY: A mix of sun and clouds with isolated flurries, trace new snow, light south wind increasing to moderate late afternoon, treeline temperatures around -13 C.

WEDNESDAY: Mainly cloudy with scattered flurries, trace to 5 cm new snow, light to moderate southeast wind, treeline temperatures around -13 C.

THURSDAY: Mainly cloudy with scattered flurries, trace to 5 cm new snow, light southerly wind, treeline temperatures around -13 C.

Avalanche Summary

No recent avalanches have been reported aside from loose dry avalanches (sluffs) from steep alpine and treeline terrain from the neighbouring Lizard Range forecasting area. Cornices are growing fragile with continued cold conditions faceting their bonds. 

Snowpack Summary

Alpine and upper treeline terrain remains heavily wind affected from last week's strong to extreme southwest winds with scouring, sastrugi, isolated pockets of soft snow and layers of hard wind slab. A hard thick crust is found below 1800 m. Near-surface faceting continues to slowly soften hard surfaces and weaken cornices. 

A solid mid-pack sits above deeply buried decomposing crust and facet layers near the bottom of the snowpack (100-150 cm deep). Avalanche activity on these layers has been sporadic and mostly triggered by large loads such as wind slab avalanches and cornice falls. Though unreactive under the current conditions, steep rocky slopes and shallow snowpacks should still be carefully assessed and approached with caution.

Terrain and Travel

  • Watch for wind-loaded pockets especially around ridgecrest and in extreme terrain.
  • Small avalanches can have serious consequences in extreme terrain. Carefully evaluate your line for wind slab hazard before you commit to it.
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.

Regioni coperte