Avalanche Advisory for 2016-01-23 07:08:57

The forecast area has not seen any widespread instability this season, however we have had consistent avalanches occuring in isolated zones across the forecast area. Some frequent producers of avalanches are the open, NW aspect of Gray Butte, northerly aspects above Castle Lake, east/northeast aspects on Ash Creek Butte, Sun Bowl and Powder Bowl on Mt Shasta. We've also seen some longer running point release slides occur from the upper slopes of Mt Shasta. Spacial variability is always a difficult thing to deal with however all these slopes have a few things in common: wind loaded, near treeline, 35-38 degrees slope angle. While of course avalanches will not be limited to these areas, they are good "indicator" slide paths and great signs that avalanche danger is present. It's safe to say that as we get more snow and wind storms throughout the winter, avalanches will continue to occur.

Several winters of poor precipitation perhaps have some of us complacent with our backcountry situational awareness. Beacon practice, safe travel techniques and being able to identify avalanche terrain is paramount.  With a normal winter upon us, more frequent avalanche occurance should be expected and it is going to be very important to be on your game each and every day you head out into the backcountry. The snowpack has experienced many changes from cold to warm temperatures, rapid accumulation of snow at times, high wind, surface hoar formations, etc.  The avalanche danger on Mt Shasta can be different than at Castle Lake or in the Eddy Range. Much of the terrain on Shasta is fairly simple terrain to navigate. Castle Lake, on the other hand, while short vertical relief, is complex terrain. In complex terrain, a blissful low angle ski can quickly become a convex rollover into a terrain trap. We cannot express to you enough that yes, it is important to read the avalanche advisory in the morning... BUT, it is even more important to be able to confidently travel and make decisions in the backcountry, to ski or not ski a slope based on real observations of the current terrain, weather and snowpack AND...be able to manage the trickiest variable of them all, the human factor. Powder fever is REAL and can be life threatening.

We have not been able to produce unstable results with tests in the lower layers of the snowpack. Moderate failures however, have been produced in top 30-40 cm of the snowpack over the week. This raises a good bit of concern as "moderate" is right in the middle. Most avalanche accidents happen at moderate or considerable avalanche danger. That is when the skiing is the best, but that's also when there is much uncertainty. Is the snow moderately stable or moderately un-stable? Moderate failures with the added 1-2 feet of new snow over the past 48 hours could have the camel's back begging for mercy... and you could be the straw.

For today, the scenario is pretty clear: We've had a good dollup of snow over a short period of time with cranking southwesterly winds. Wind and storm slabs are certain. A couple crust layers near the top layers of the snowpack could act as the bed surface for new wind and storm slabs. Wind can deposit snow onto leeward slopes 10x faster than falling snow. This means potentially thick wind slabs with serious consequence should you hit the sweet spot. Storm slabs will lurk and near treeline slopes will be the best place for storm slabs. Above treeline is always tricky... sometimes the wind simply blows the snow away. Wind loaded, mid slope starting zones in gullies are common on Shasta as ridgelines typically get blasted. Leeward ridgelines should always be suspect, pretty standard, but mid-slope starting zones can be stumbled upon without warning as you ski down a seemingly nice looking bowl or gully. Fortunately, many mid-slope starting zones are not that steep, but mid-slope, wind loaded convexities (steep roll-overs) should be your "watch out" situation.

Remember, your skin track up the hill is just as important as your ski line down. Choose safe up tracks... don't just follow the skin track that is set if you're not comfortable with the route. Breaking trail is a lot easier than getting caught in an avalanche. Also, tracks on a slope does NOT mean the slope is safe.
Only one at a time on a given slope. Use safe zones and make sure they are safe! Use good communication between group members. Avoid large groups. Talk about your route plan for the day and be ready to adjust your plan as you notice unstable snow such as shooting cracks, whumphing, recent avalanches, and/or rapid accumulation of snow.

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LOCAL AREA ROAD, NORDIC and SNOWMOBILE PARK STATUS:

The Sand Flat cross country ski trails are in great shape and ready for your cross country skis or snow shoes. These are backcountry trails marked with blue diamonds on trees. Trails are not groomed.  Snow shoers, please blaze a parallel trail to cross country skiers staying out of the skin track. These trails can be accessed via the Everett Memorial Highway. Thank you, and enjoy!

The Mt Shasta Nordic Center is open! These beautiful, groomed trails can be accessed via the Ski Park Highway. http://www.mtshastanordic.org

The Pilgrim Creek & Deer Mountain Snowmobile Parks are open! Trails are being groomed currently. Head to our "Education" tab on our website and find the snowmobile section for trail information, grooming status and other sledder resources!

The Castle Lake road is plowed to the Vista Point. The Everett Memorial Highway is plowed to Bunny Flat.

The Five Red Flags of Avalanche Danger any time of year include:  1) Recent/current avalanche activity  2) Whumphing sounds or shooting cracks  3) Recent/current heavy snowfall  4) Strong winds transporting snow  5) Rapid warming or rain on snow.