Avalanche Advisory for 2015-03-15 06:41:18

To everyone's dismay, between a tenth and quarter inch of rain on snow occured yesterday with the freezing level upwards of 10,500 to 11,000 feet. Needless to say, visibility was poor, conditions were wet, and Bunny Flat was as vacant as I've seen it this season.

While the upper mountain probably received a couple inches of new snow that got blown around by strong southwest winds, I was never able to catch a glimpse to confirm. I would suspect that most areas remain scoured from the strong SW wind, however more protected pockets could host small wind drifts and potentially a slab... that said, if you know Mt Shasta at all, you know that there are few "protected" areas on the upper mountain and thus is likely scoured!

From limited observations yesterday due to poor visibility, the snowpack remains stable and strong and the rain on snow did not cause any instabilities. This current storm is still holding some lingering showers for today/tonight and temps will also cool a few degrees, lowering snow levels to 8,000 to 9,000 feet. Perhaps we will start the week with a skiff of new snow near and above treeline. Southwest winds will continue today and begin to die off tonight. The week looks quiet - the next chance of weather is predicted for next weekend. Moisture amounts are unknown, but colder temps are forecasted to bring snow levels to as low as 5,000 feet. One day at a time for now...

Below treeline, tree wells are showing and dirty snow exists. March isn't over yet and many are still holding out for a couple more good storms this season!
For all users, LOW danger exists and normal caution is advised. Continue to always use safe travel methods: carry situational awareness on your skin up the mountain, choose safe routes and watch for what others are doing, ski one at a time, stop in safe zones!

All photos from N Meyers on 3.13.15, clockwise from top left:

*The Doc, deep in the heart of the Mt Shasta backcountry
*Old Ski Bowl ski
*Some roller ball evidence on a southwest/west facing slope
*A great look at Sargents Ridge and The East Side of Mt Shasta

For folks that plan on climbing Mt. Shasta:  Route conditions on Casaval Ridge, Sargents Ridge, and Avalanche Gulch are currently good.  That being said, there are some objective hazards to be noted.  Snow surfaces will be firm and smooth in the early morning hours and will make for "slide for life" conditions.  Should one slip and fall and are unable to self-arrest, a long tumble is a possibility.  Ice fall from rime ice that still partially covers the Red Banks and other rock outcroppings is happening, even in the early morning hours.  A helmet, crampons, and a mountain axe are necessary equipment and should be used. 

Castle Lake and Mt Eddy zones are still hosting a shallow snowpack. All areas below about 6,000 feet in the forecast area are hosting patchy snow with dirt showing around trees and in sunny spots.  For Castle Lake, skiing is out of the question at this point due to lack of snow.

Report your observations to the MSAC! A photo, a few words... send them in! (nimeyers@fs.fed.us or 530-926-9614)

Sand Flat Winter Trails: OPEN, trail conditions are firm and getting thin with some tree debris on snow surface. 

Pilgrim Creek Snowmobile Park: OPEN, however due to lack of low elevation snow, one must drive up the road several miles before enough snow is encountered. One CANNOT DRIVE over Military Pass. Snowmobiling is not recommended due to low snow depths.

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Terrain:  Remember most of the terrain that we like to play on is greater than 30 degrees.  Avalanches are possible on anything steeper than 30 degrees.  Avoid cornices, rock bands, terrain traps and runout zones of avalanche paths.

Weather:  Most of our areas avalanche danger will occur 24-48 hours after a storm. We still can see persistent weak layers from time to time and we always will be sure to let you know about that!  Heed the basic signs: Wind (significant snow transport and depositions), Temperature (rain/snow/rain/snow, which in turn weakens the snowpack), and Precipitation (Snow or rain add weight and stress to the current snowpack).

Snowpack:  If snow accumulates, give the snowpack a chance to adjust to the new snow load before you play on or near steep slopes (greater than 30 degrees).  Most direct action avalanches occur within 24-48 hours of recent snowfall.  Watch for obvious signs of snowpack instability such as recent natural avalanche activity, collapsing of the snowpack (often associated with a “whumphing” sound), and shooting cracks. If you see these signs of instability, limit your recreation to lower angle slopes.

Human Factor: Don’t forget to carry and know how to use avalanche rescue gear. You should NOT be skiing or climbing potential avalanche slopes without having beacons, shovels, and probes.  Only one person in a group should be exposed to potential avalanche danger at a time.  Remember, climbing, skiing, and riding down the edge of slopes is safer than being in the center.  Just because another person is on a slope doesn’t mean that it is safe.  Be an individual!  Make your own decisions.  Heed the signs of instability: rapid warming, “whumphing” noises, shooting cracks, snowing an inch an hour or more, rain, roller balls, wind loading, recent avalanche activity.

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