Continental

Problemi valanghivi

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  Loose Wet

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alta quota
  • Limite del bosco
  • Sotto il limite del bosco

  Probabilità

  Likely

  Dimensione

  1–2.5

  Rain has occurred intermittently for the last 48 hours along the coast, with the freezing line climbing in elevation as well.  It looks as though the warmest weather occured overnight with temperatures reaching 36° at the Nicks station at 4200'.  This would put the freezing line somewhere above 5000' overnight.  The recent increase in temperatures along with moderate rain will make it likely for  human triggered and natural wet loose avalanches to occur.   Recognizing where avalanche activity may occur will depend upon terrain shape and elevation.  

  When dealing with a wet loose avalanche problem it is very important to pay attention to not only the terrain you are travelling on , but the terrain that is above and below you.  The size of wet avalanches that can occur is directly correlated to the size of the slope in question and the depth that warm temperatures have penetrated into the snowpack.  The larger the slope, the more potential there is for snow to be entrained, increasing the mass of a potential avalanche.  The depth that above freezing temperatures have penetrated the snowpack will dictate the amount of entrainment that can occur.  Recognizing slope size may be difficult today as cloud cover may reduce visibility.  The depth of warmth in the snow can be tested by digging into the snow to see at what point the snow becomes dry.  If a very hard snowball is readily made than above freezing temps are present in that snow,  If water can be squeezed out of the snow, that snow is very susceptible to wet loose failure in terrain steeper than 35°.  Paying attention to the terrain below you is very important as well as terrain traps such as creek bottoms can greatly compound the consequences of being carried in a wet loose slide.

  The freezing line is forecasted to steadily descend during the day today through tomorrow along with a continuation of precipitation.  This will allow rain to switch back to snow at upper elevations and slowly move down the mountains over the next 24 hours.  This will slowly decrease the wet loose hazard above the freezing line.

  

• 

  Storm Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alta quota
  • Limite del bosco
  • Sotto il limite del bosco

  Probabilità

  Likely

  Dimensione

  1.5–2.5

  Fairly steady precipitation has occurred over the last 48 hours with the freezing line moving up to an estimated 5000' on 12/10.  There have been no observations at these upper elevations during this storm due to low visibility making travel unsafe at upper elevations.  Our highest weather station was affected by rain yesterday, so upper elevation snow totals are just a guess.  We can assume that 1-2 feet of new snow has accumulated with the higher amount of that range near the coast.  Southeast winds have been moderate to strong through the majority of the storm, expect for wind direction to be influenced by local terrain to some extent.

  If you manage to make it above the freezing level today expect to find new storm slabs that are susceptible to human triggers 1-2 feet in depth.  Pay attention to the depth, distribution, and sensitivity of new snow.  Watch for red flags such as recent avalanche activity, shooting cracks, and collapsing that would indicate unstable snow.  Avalanches that are triggered will have the potential to step down into the layer of snow that accumulated last week.  

• 

  Glide Cracks

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alta quota
  • Limite del bosco
  • Sotto il limite del bosco

  Probabilità

  Unlikely

  Dimensione

  2–2.5

  Numerous Glide Cracks exist on the North facing Buttressess of Nicks through Cracked Ice between 2000'-3000'.  Identify where these are if you decide to travel in this area and avoid traveling on or below them.  Glide cracks act differently than all the other avalanche problems and can fail even when the general hazard is low and without signs of instability.  Stability of Glide cracks has more to do with the relationship with the friction at the ground and less so to do with the weather that is effecting the surface like other avalanche problems.  Little is known about assessing glide cracks, so travel advice is simple: Avoid them.