Bollettino valanghe

North Columbia

Apr 18 – 19, 2022Avalanche Canada
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Archiviato · scaduto 4 years ago

Pericolo valanghe

Wed
Thu
Alta quota
2 · Moderato
Limite del bosco
2 · Moderato
Sotto il limite
1 · Debole

In sintesi

Be mindful of reactive slabs forming with new snow, the deepest deposits will be in areas loaded by wind. Bump the hazard to Considerable if you find more than 20 cm fresh snow in your riding area.

Problemi valanghivi

  • Wind Slabs

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

    Upwards of 15 cm flurries is forecast to accumulate by the end of Tuesday, with localized areas getting up to 25 cm. New snow is not expected to bond well with the old surfaces, particularly on the old crust. Expect slab reactivity to increase through the day, especially in wind-loaded terrain.

  • Cornices

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Unlikely
    Dimensione
    1.5–3

    Cornices may be weak and reactive to human triggers. Give them a wide berth when travelling on ridges. They are a significant hazard alone and may produce large slab avalanches as they fall onto the slope below. Cornice falls are more likely when the weather is sunny, warm, or windy.

Weather Forecast

MONDAY NIGHT: Cloudy with flurries, 5-15 cm. Treeline low -6 C. Increasing southeast-southwest wind, 15-30 km/h.

TUESDAY: Wet flurries and snow, another 5-10 cm through the day with rain below 1400 m. Treeline temperatures rising to -2 C. Wind 15-30 km/h from the west. 

WEDNESDAY: Partially cloudy. Treeline temperatures rising to +1 C, freezing level reaching 1700 m. Light wind from the south. 

THURSDAY: Mix of sun and clouds. Treeline temperatures rising to +2 C. Light winds from the southeast.

Avalanche Summary

Avalanche activity the last week has primarily been large cornice failures on north and east-facing slopes. For the most part, these have not triggered avalanches on the slopes below.

Snowpack Summary

At treeline and higher, fresh snow will cover old wind slab and wind press, and up to 20 cm of old snow. This sits on a melt-freeze crust all aspects to 2000 m and mountain tops on solar aspects. Another prominent crust layer is found 30-70 cm deep. 

Cornices are very large and exposure to slopes beneath them should be minimized, especially if the weather is sunny, warm, or windy. The snowpack deteriorates rapidly at lower elevations.

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Closely monitor how the new snow is bonding to the crust.
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.

Confidence

Moderate - Uncertainty is due to the track & intensity of the incoming weather system.

Regioni coperte