April 4, 2016

Observations

Eagle River: South Fork headwaters

Red flags (obvious signs of instability):

  • Isolated and very thin, micro wind slabs upper elevation leeward terrain

Weather:

  • Mostly cloudy with alpine temps in the upper 20s and light to moderate SE wind (not much snow available for transport – some spindrift at upper elevations later in day as winds increased to more steady moderate)

Surface conditions:

  • Generally solid and supportable melt-freeze crust to 3500′ across all aspects
  • Above 3500′ snow is variable depending on aspect and steepness (e.g. dust on supportable crust, superficial and carve-able crust, boot-top deep powder)

Snowpack:

Hard freeze the past couple nights and colder daytime temperatures have “locked-up” the snowpack and greatly improved stability.  Clouds and wind today prevented necessary softening of the crust for the development of quality corn; not a good day to harvest.  Sheltered upper elevation northerly terrain holding quality powder, but generally the runs are variable lower down due to recent abnormally warm temperatures and wet snow runoff from nearby steep, rocky terrain that has put frozen debris on aprons.

With significant daytime warming and solar radiation, the melt-freeze cycle will continue through the season with avalanche danger rising each afternoon-evening.  Watch for wet avalanche danger on solar aspects, and rockfall and sluffs on northerly aspects (especially if warming is pronounced).