Silver Peak

We toured on Silver Peak today to assess the snow surface refreeze that finally occurred last night following several days of no snow surface refreeze. The approach has melted out in some areas, but is still easily passable. Last night's snow surface refreeze was driven by below freezing air temperatures rather than by radiational cooling alone. Residual wet snow ranging from F to 4F hardness existed directly below the surface melt-freeze crust that formed last night.

The surface melt freeze crust's thickness and hardness were consistent both on open slopes and under forest canopy. The strength and thickness of the refreeze increased with elevation. At the Pole Creek trailhead at 6,000' we encountered a snow surface refreeze measuring 4 inches thick at P hardness. At 8,000' on Silver Peak the snow surface refreeze was 5 inches thick at K hardness. 

By 10:30 am, this refreeze was well into melt phase on sun exposed slopes. By 11 am, the hardness had decreased to 1F hard at 8,200' and to 4F hard at 7,500' on open E to SE aspect terrain. It appeared that the snow surface refreeze would lose ski supportability today on solar aspects while at the same time remain frozen all day on polar aspects. There was a trace of new snow on top of the surface crust.