Bollettino valanghe

Cariboos

Jan 28 – 29, 2013Avalanche Canada
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Archiviato · scaduto 14 years ago

Pericolo valanghe

Wed
Thu
Alta quota
3 · Marcato
Limite del bosco
2 · Moderato
Sotto il limite
2 · Moderato

In sintesi

Ratings are based on the region staying mostly dry on Tuesday morning. If you do see significant snowfall (20+ cm) by noon on Tuesday, consider ratings to be High / Considerable / Considerable.

Problemi valanghivi

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Unlikely - Possible
    Dimensione
    2–5
    Two surface hoar layers lie buried under the surface, one approximately 40cm down and the other approximately 80cm down. Both are reported to be patchy and variable in distribution. Most likely triggered on steep convex rolls at treeline or below.
  • Storm Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–4
    Recent storm snow is settling into a soft slab in many areas. Where this overlies surface hoar or a crust it will become increasingly touchy. Pockets of wind slab exist behind ridges where the snow is protected from a S or W wind. Watch fat pillows.

Confidence

Fair - Intensity of incoming weather is uncertain

Weather Forecast

Synopsis: Northwesterly flow will bring a series of moderate or locally heavy pulses of precipitation to the region through the forecast period.Tuesday: Should stay cold (-12C) and dry for the first half of the day. Moderate or locally heavy precipitation beginning in the afternoon, with 10-20 cm expected by Wednesday morning. The heaviest snowfall is likely to be found to the north and east of the region. Treeline temperatures rising to around -8C. Northwesterly winds, gusting to 60km/h at ridgetop during the afternoon.Wednesday: Further light snowfall, around 5 cm. Treeline temperatures peaking around -2C. Strong northwesterly winds gusting to 50km/h at ridgetop.Thursday: Dry, cold (-12C) with generally light northwesterly winds.

Avalanche Summary

No new avalanches were reported through the weekend. On Friday, a couple of small (size 1) avalanches were triggered on convex rolls by ski cutting on south aspect slopes.

Snowpack Summary

Around 40-50 cm recent new snow has settled into a 20-30 cm soft slab overlying a weak layer comprising of facets at higher elevations, surface hoar on shady slopes, and a sun crust on solar aspects. The recent new snow sitting above this interface has been slowly consolidating from fresh powder into a more cohesive slab. As this process continues, the avalanche character will change from relatively harmless loose sluffs to more dangerous slab avalanches. However, note this upper weak layer has been reported to be patchy and variable in distribution. A mid-pack layer buried in early January surface hoar layer is down 70-90 cm. While this layer is still on the radar of professional observers, with most likely trigger points being on steep rolls below 1600 m, there has only been one small avalanche (size 1 at 1200 m on a north aspect) reported on this layer from the region for approximately 10 days.

Regioni coperte