Lawinenlagebericht

Continental

Valdez Avalanche Center
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Lawinengefahr

Hochgebirge
2 · Mässig
Waldgrenze
2 · Mässig
Unterhalb
2 · Mässig
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Veraltet — dieser Lagebericht ist last year abgelaufen. Du siehst vergangene Verhältnisse, nicht den aktuellen Bericht.

Kernpunkte

The avalanche hazard is Moderate at all elevations.  Human triggered avalanches are possible 1-2 feet in depth involving the most recent snowfall.  Wet loose natural avalanches are possible.

Avalanche Forecasts are issued Wednesday-Sunday at 8am.  

Lawinenprobleme

  • Persistent Slabs

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Possible
    Größe
    1–2.5

    The period from 3/16-3/19 saw snowfall totals that ranged from nearly 3 feet at upper elevations near the coast to ~20 inches near Thompson Pass and less than a foot in the Continental zone.  This new snow fell on a widespread layer of buried surface hoar, which is a variety of weak snow that has the potential to create instability in the upper snowpack that can persist for long periods.

    After 3 days of observation, the sensitivity and distribution of this weak layer is coming into better focus.  The snowpack along the Thompson Pass road corridor has not shown signs that a reactive weak layer is present.  In tact buried surface hoar has not been identified in snowpits in terrain that drains to the road.  Expect buried surface hoar to remain reactive in isolated pockets of steep terrain near Thompson Pass.

     Reports of identifiable buried surface hoar in snowpits and human triggered avalanches have come from glaciated valleys that are colder and more protected than the core Thompson Pass area.  Instability is expected to be more prevalent in these areas.  Don't assume that the same snowpack structure and stability exists in all areas.  Continued assessment is advised especially when branching out into new zones.

    The sensitivity of this layer is expected to be variable depending on location creating a situation where snowpack assessment can be challenging and confusing for users.  Keep in mind that the terrain in the Thompson Pass area is vast and diverse.  Just because you experience good stability in the Thompson Pass road corridor does not mean the same stability will exist in more remote zones.  More observations are needed to gain a better understanding of the sensitivity of this persistent weak layer.

    Human triggered avalanches remain possible that would be large enough to injure, bury or kill a person.

     

    (3/19/2025)

     Natural avalanche in the books that likely failed on 3/16 BSH

    Photo: Eagan Gleasson

  • Loose Wet

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Likely
    Größe
    1–2

    Sunny skies are forecasted today which will increase the likelihood for wet loose avalanches to occur.  Sun and temperature crusts have formed on solar aspects that will initially prevent wet loose activity.  Once the heat of the day breaks down these crusts wet loose activity will become possible.  The first area to become active will be steep rocky terrain where the suns energy is more effectively absorbed by the dark color of rocks and then transmitted into the surrounding snow surface.  Pay attention to where the sun is in the sky, wet loose hazard will peak on a slope when the sun becomes perpendicular.

    Wet loose activity is a secondary concern to problem 1 listed above.  Steep terrain that produces wet loose activity will also have the potential for slab avalanches to fail naturally or be human-triggered.   Avoid steep terrain that is being heated up by the sun.  Even small slopes can be dangerous if they are above terrain traps or exposure.  

    This is the time of year when snow begins to naturally shed off steep Southerly terrain.  Avoid exposure to these areas during the heat of the day.

Avalanche Discussion

Observed Avalanche Activity last 72 hours: 

Numerous D1-D2 Natural and Human triggered avalanches reported from all forecast zones over the last 3 days.

Forecast Discussion:

Assessment of the snowpack currently revolves around a layer of buried surface that is beneath the 1-3 feet of new snow that fell last week.  This should be everyone's main focus when deciding if a slope is safe to ride.  After 3 days of slope testers pushing into steeper terrain this layer has not shown a high sensitivity along the Thompson Pass road corridor, however human triggered avalanches have been reported in the high and cold glaciated areas to the south of Thompson Pass.  Try not to be lulled into complacency, conditions are far more dangerous than they were just a week ago.

Slopes that are directly in the sun will gain cohesion and can increase slab sensitivity during the day.  Most of the natural activity that has been noted has been on south aspects, likely due to an old melt freeze crust acting as an effective bed surface.  As days continue to warm West-Northwest aspects may increase in sensitivity during peak warming as slabs gain more cohesion.

This setup is not only dangerous but can be difficult to assess.  The first person to ski a slope is not necessarily the one that will trigger an avalanche, a slope can fail after numerous tracks have been laid down.  Digging snowpits is a good tool, but can give misleading results as buried surface hoar can be easily missed depending upon where you dig.  In addition, ECTN results are not necessarily an indication that the slope is safe. Deep burial of surface hoar layers may create false stable results in pit tests. It is important to consider that we have several factors pointing to an unstable snowpack. These include: a persistent buried weak layer, a thick cohesive slab, recent avalanche activity, and increasing temperatures in many areas.   Conservative terrain choices and cautious route finding are recommended.  Only expose one person to a slope at a time, know your safe zones maintain good communication with your group, and watch out for other groups that may be recreating in the same area.

Additional Information:

Watch out for cornices. A couple of cornice falls have been observed in the Continental region.

A weather and snowpack season history is available by clicking on the Season Summary tab which is located below the bottom line statement once you have entered the full forecast.

Season Snowfall Data

Location 24 hour Snowfall Inches- 3/22 24 hour Snow Water Equivalent Inches Height of Snow March Snowfall Inches Season Total Snowfall Valdez    0    0    58     18 N/O     Thompson Pass    0    0   N/O     ~24    ~500 Nicks    0    0    146    15 N/O 46 Mile    0     0   22    5 N/O

Abgedeckte Regionen