Bollettino valanghe

Central Cascades

Central Oregon Avalanche Center
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Pericolo valanghe

Tue
Alta quota
3 · Marcato
Limite del bosco
3 · Marcato
Sotto il limite
2 · Moderato
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In sintesi

Another round of snowfall on Monday will keep avalanche danger elevated.  Wind Slab avalanches will be likely on East and NorthEast facing slopes where the wind has blown and packed the newest snow.  The size of these avalanches will grow throughout Monday as more snow falls and the wind continues to move snow.  Avalanches are also possible below treeline.  Early on Monday these will be shallow Loose snow avalanches, but know that they will increase in size and possibly propogate farther as more snow falls later in the day.

Problemi valanghivi

  • Wind Slabs

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

    Moderate and Strong winds from the SouthWest have been blowing snow onto East and NorthEast slopes and creating wind slabs.  Wind Slabs occurr at treeline elevations and in the alpine where the wind has the greatest ability to blow freely and move snow.  On Sunday at Tam MacArthur rim we could see Wind Slabs beginning to form (see picture of cracking surface snow).  As more snow falls on Monday and the wind continues to blow Moderately and Strongly from the West and SouthWest these avalanches could become large enough to bury or injure a rider.

    (2/26/2023)

    Cracking in Wind Deposited snow

    Photo: Gabriel Coler

  • Loose Dry

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely
    Dimensione
    1

    On Sunday we saw lots of Dry Loose avalanches that were triggered both naturally and by skiers.  They were all small and were very predictable (nearly garaunteed on any slope that we skied over 35 degrees).  As more snow falls on Monday they will increase in size.  Be careful on larger slopes when terrain traps are present where an otherwise harmless Dry Loose avalanche could have greater consequences.

    (2/26/2023)

    Dry Loose avalanche from early in the day on Sunday.  NorthEast slope, at treeline.

    Photo: Gabriel Coler

  • Storm Slabs

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

    Storm Slab avalanches will be possible by late in the day on Monday.  As storm totals from Sunday and Monday reach the 1 ft.  mark I'll be paying particular attention to whether or not the surface snow is cohesive.  The snow that fell on Sunday was very light and dry and could provide a weak layer for the next round of snowfall.  If that snow has some cohesion we could see Storm Slab avalanches.  Your best bet for determining whether Storm Slabs are possible are your simple skin track observations like test slopes and hand shears.

Avalanche Discussion

Snowfall totals by Sunday evening seem to be around 15 cm.  With more wind and snow in the forecast for the forseeable future, our avalanche concerns will be focused on the new snow and direct action avalanches (Storm Slabs and Wind Slabs).  There is a melt/freeze crust (Feb. 21) throughout most of our terrain that is now burried 45-55 cm.  This is a great landmark if you are digging for stability tests.  We haven't found any significant weak layers beneath this crust.

Regioni coperte