Continental

Problemi valanghivi

• 

  Storm Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

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

  Probabilità

  Likely

  Dimensione

  1–2

  Storm slabs will be the most likely problem to encounter for travelers seeking soft snow conditions today. Although there is little in the way of new snow along the road corridor, we have been finding a foot or more of recent snow above 4000 feet. Poor bonding to weak underlying surfaces has been observed in many areas, and a few human-triggered avalanches have been reported.  If you find good riding conditions today, expect there to be a strong possibility of triggering a storm slab up to a foot deep. If snow surfaces begin to warm and stiffen/moisten, you can expect the hazard to be rising in your area. Using cautious travel protocols while testing snow stability on small test slopes and hand pits is recommended. As always, if you see shooting cracks underfoot or experience the collapse of recent snow, you can be sure it is unstable in your area. 

  

• 

  Loose Wet

  N

  NE

  E

  SE

  S

  SW

  W

  NW

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

  Probabilità

  Very Likely

  Dimensione

  1–2

  Over the last 24 hours, we experienced a widespread naturally occurring wet loose avalanche cycle. Hundreds of small to large solar-triggered loose avalanches were observed throughout our forecast area, especially in the maritime zone. Today, we expect similar conditions to affect solar aspects all the way up to ridgetops. With mild overnight temperatures and sunny skies this morning, it can be expected that this hazard will begin early today and continue through the day on sunny slopes. East slopes will be the first to be affected and will be followed by the South and West slopes later in the day, and possibly the NorthWest in the early evening. Pay attention to the aspect you travel on today, and the timing of sun exposure. Keep in mind, slopes that are stable on your way out in the morning could become hazardous on your return trip. Signs of instability associated with this problem will be easy to spot and include moistening of surface snow, "roller balls", and small loose slides. If you see any of these, it will be best to stay off steep slopes where even a small wet slide could be hazardous.  

• 

  Persistent Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

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

  Probabilità

  Possible

  Dimensione

  2–3

  A couple of large human-triggered avalanches yesterday in No Name Creek appear to be persistent slabs. 

  We have had an unusually weak snowpack this season with a variety of persistent weak layers. Over the last month, buried weak snow has been under relatively low stress due to the cold temperatures and lack of snow. Recent snowfall followed by significant warming has begun to stress our snowpack, increasing the chances that a traveller could trigger a persistent slab 2-3+ feet deep.  Unfortunately, this problem is hard to assess and will show no signs of instability before an avalanche occurs. Using cautious travel protocols and terrain selection are the only ways to mitigate this problem, which is less likely but more hazardous than the previous two problems. Avoid travelling on or below steep alpine slopes when possible. If you decide to ski steep terrain, do so one at a time and have planned escape routes in the event of a large avalanche

  Deep Persistent Slab: Weak snow buried over a meter deep is increasingly common as you move North through our forecast zones, with the Continental zone being the most concerning. Although it still remains unlikely to trigger this layer, areas that have been scoured from strong northeast winds now have a shallower snowpack, making this layer closer to the surface and potentially easier for a rider to trigger. The best way to check for deeply buried weak snow is by using your probe to feel for decreasing resistance below stiffer slabs. 

  This is a low-likelihood but high-consequence problem that may become more of a concern as warming temperatures penetrate deeper into our weak snowpack in the near future.