Decreasing temperatures along with accumulating snowfall coming to an end has allowed the most recent storm snow to settle to a degree.  Human triggered avalanches will be possible today up to 3 feet in depth.  North winds are forecasted to increase to moderate today.  The most likely place to trigger an avalanche will be in steep convex terrain or in areas where active or recent wind loading has occurred.  In the Maritime zone the 1/25 rain crust exists below 2500′ and has been losing strength, creating a potential weak layer.  Human triggered avalanches are possible  at that interface.  Otherwise the new snow/old snow interface is currently our main concern.

The weather prior to the latest storm (overcast skies, light snowfall and mild temperatures) was not favorable to form facets (weak snow) at or near the surface in most areas.  This will allow the storm snow to bond well with the snowpack once given ample time.  Very little natural avalanche activity was observed with this storm which increases our confidence in a lack of a persistent weak layer at the new snow/old interface.  DOT mitigation efforts were able to produce several D2-2.5 avalanches within the storm snow at the tail end of the storm.  No step downs were observed.  

Even a strong snowpack has flaws, in addition our forecast area is  vast, diverse and stability may vary from place to place.  It will be important to pay attention to how well the new snow snow has bonded and recent wind loading in the area that you choose to travel today.  Watch for signs of instability such as shooting cracks, collapsing or recent avalanche that would indicate unstable conditions.  

Weak snow continues to exist near the base of our snowpack in all three climate zones.  This weak snow has recently been under increasing pressure as heavy snowfall and strong winds occurred 2/5-7.  The last recorded avalanche activity at this layer occurred during the 1/23-25 storm on Nicks Buttress / ~3500’/ north aspect (see avalanche activity section).  The amount of snow and wind our area just received was significant, and was a great strength test of weak snow near the base of our snowpack.  No avalanches have been observed that failed or stepped down to this layer during the latest storm.  Human triggered avalanches are currently unlikely to occur that fail on weak snow near the base of our snowpack.

Faceted snow near the ground has been found to vary significantly from place to place.  In most locations this snow has been found to be rounding (gaining strength) and unreactive in stability tests.  In thin areas of the snowpack these facets are significantly more developed.  The most likely places to affect weak snow near the ground will be in areas where the snowpack is thin.

If you find it is possible to push a ski pole to the ground in areas you travel.  Assume that a weak faceted snowpack exists in that location, that could act as a trigger point.

Depth hoar from Nicks Buttress ~4000′ North aspect 1/31.