Continental

Avalanche problems

• 

  Persistent Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpine
  • Treeline
  • Below treeline

  Likelihood

  Possible

  Size

  1.5–2.5

  The primary avalanche concern remains a layer of buried surface hoar (BSH), situated beneath 1-3 feet of settled storm snow in isolated areas. Today's forecast predicts light snowfall, primarily coastal, which is not expected to heighten the risk of avalanches at this layer. While human or machine triggers might initiate avalanches of 1-3 feet in depth at this layer in protected areas on the northern side of the compass in the Continental zone, such occurrences are less likely in the Maritime and Intermountain zones due to the layer's much more sporadic presence.

  Recent mild weather over the past five days has contributed to increased stability and reduced chances of human-triggered avalanches. This is supported by observations of numerous slope testers exploring steeper terrains without any avalanches reported in the last 48 hours. Yet, it's likely that mechanized skiers have been steering clear of areas most susceptible to this weak layer.

  It's important to recognize that this type of weak layer is considered persistent because its instability can last for prolonged periods and is unpredictable. These layers may become dormant and later experience periods of increased sensitivity, particularly during warm spells or heavy snowfalls. Continue monitoring the snowpack for this layer, especially in unfamiliar drainages. While snowpits are valuable, they can be misleading, as identifying this layer becomes more challenging with age and deformation. Look for a change in hardness (weaker) at the lower end of the settled storm snow, just above a firmer layer of wind-affected snow from late February.

  

• 

  Loose Wet

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alpine
  • Treeline
  • Below treeline

  Likelihood

  Possible

  Size

  1–2

  Wet loose activity will become possible below 2000' on the southern half of the compass as the sun begins to heat the surface of the snow.  Cloud cover today is likely to limit this activity.  However, temperatures were already 33 at sea level at 6 am which will allow any sun that does occur to have a more rapid effect on the snowpack.

  Recently, wet loose activity has decreased over the last couple of days as the initial shock to the upper snowpack from rising temperature has already taken place with a lot of the 3/16 storm snow already avalanched away on southerly aspects and low elevations.  Hard wind damaged snow beneath and thick melt freeze crusts make it more difficult for the sun to break down and will make wet loose activity lower in volume and distribution.  Cloud cover is expected later today, which will also limit the amount of warming that happens at the surface.

  Wet loose avalanches offer clear instability indicators and are highly dependent on slope aspect. Monitor the sun's impact on the snow surface closely. Wet loose conditions become a concern when over 4 inches of snow becomes moist, particularly on steep, rocky slopes. The avalanche hazard does not affect all aspects simultaneously but  starts on east-facing slopes, shifting to south and then west. Stay vigilant to which slopes are most affected by solar heating and to what extent.