Bulletin d’avalanche

Mt Hood

Jan 19 – 20, 2015Northwest Avalanche Center
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Archivé · expiré 12 years ago

Danger d’avalanche

Wed
Alpin
2 · Modéré
Limite forestière
2 · Modéré
Sous la limite
2 · Modéré

Points saillants

Watch for locally sensitive wind slabs on lee slopes near and above treeline and sun affects on steeper solar slopes Tuesday afternoon.  

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    1
  • Storm Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    1

Detailed Forecast

Tuesday should be partly to mostly sunny with a gradual warming trend. Recent shallow storm snow should continue to settle, but sunshine and increasing temperatures in the afternoon may activate loose wet avalanches predominately on steeper southerly slopes. Especially watch above treeline, where more snow is available for entrainment and could funnel you into a terrain trap.  

Also, there may be pockets of sensitive wind slab mainly on N-SE aspects near and above treeline.  

 

Snowpack Discussion

Strong southwest flow carried a warm and wet front across the PNW Saturday night. This front tapped subtropical moisture pushed snow levels pretty high on Mt. Hood resulting in 3.5 - 4.5 inches of rain at NWAC sites. A cooling trend Sunday along with another inch of water ended as 4-5 inches of new snow between 5-6000 feet by Monday morning. 

NWAC observer CJ Svela was at Timberline on Sunday. He found consolidated P and 1F layers in the top meter of the snowpack but no avalanche activity in this area. Mt. Hood pro-patrol reported wind transport Mon AM leading to a thin and soft wind slab above treeline. West winds eased off more quickly than forecast Monday and new wind transport was not likely significant. 

The mid and lower snowpack at Mt Hood should also mainly consist of melt-freeze crusts and stabilized rounded grain layers from warm stretches so far this winter. 

Régions couvertes