The Bottom Line: Fresh snow is available for transport by forecasted SE winds. Lingering wind slabs could also still be reactive.  N NE and NW slopes may be harboring windslabs, there are cornices building on ridges, and gullies/ other terrain features maybe cross loaded. The poor structure is widespread, additional stress from this weeks snow has being added, don’t be the trigger that tips the scale. Control what you can: human factor and terrain. 

Cold fluffy snow is beautiful and fun, but can also produce dry-loose and slough. Keep this in check.

Terrain management is critical! Be prepared for an avalanche that could step down to deeper instabilities, creating a slide that could break very wide, and take out all the “safe” zones on a slope. Be extra careful not to group up in places that an avalanche can reach. Be diligent and patient, practice good group management, communication and decision making. Do not ski/ride on the same slope as another group. Travel one at a time or with enough spacing so that only one person is exposed to an avalanche path at any one time. 

Protected means preserved. When seeking out wind protected zone, remember that wind-protected pockets may be harboring these dangerous weak layers. 

Buried Surface Hoar Layers:

• Jan 25th melt freeze crust is about 1-2 feet deep (with recent winds and snow, there is a lot of variability on depth of this widespread layer) sitting on top of it are near surface facets, and buried surface hoar from Feb 1-4.
• January 10th surface hoar is now buried about 3-4 feet deep.
   

Feb 10 Flower tree-line small wind slab shooting crack on isolated feature.

Feb 10 Flower tree-line 2600′ N NE aspect ECTX.  Found Jan 25 melt freeze/facet sandwich ~2’ down from surface.  Also noted a thin layer of rounding facets in the mid pack and a thick layer of depth hoar.

Old Melt Layers and Crusts:

• Dec 31 surface hoar layer is present in the Transitional and Pass zones, about 5 ft deep. This layer has been active in pits, and caused some natural avalanches in early January.
• A buried persistent weak layer about 7+ feet deep (The “Big Warmup” Layer, Formed Nov 17th) is still a concern. Numerous natural avalanches observed 1/27 likely on this layer.
• A wide safety margin is necessary. This setup could produce avalanches that break wider than expected, and are most likely to be triggered from shallow trigger points like rocks or small trees. You could ride the same slope numerous times until that right spot produces a large destructive slide.

“Big Warmup” facet layer in the Transitional Zone at 2500ft on Jan 2 with test results ECTP18 that demonstrated propagation potential on this layer.

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Pit at Old Faithful, 2500’, East aspect on Jan 12. A 5″ thick layer of facets down 170cm. Also, observation noted faceted surface conditions.

Depth Hoar at the Ground (Above 3,000′):

• October snow followed by long cold snaps created depth hoar at the ground in most areas.
• You are most likely to human-trigger this layer from shallow spots around rocks, or trees, or have a surface avalanche step down to the ground on this layer. Any slides that break to the ground are likely to be deadly.

Photos shows 6-9mm advanced depth hoar at the ground down 180cm with ECTP 25 down 80cm on facets below a crust in the Haines Pass Zone at 4,000ft on a NE-aspect.