On Thursday, February 4th, the ski trails at Alturas Lake looked very good, when they could be seen at all. Shimmering, shifting grey white light made meadowed trails into vibrating shadowless snowscapes, only the slightest sight of a trailside stake pointed the way.  Not to worry, Friday, the 5th is a beautiful blue sky day with clear visions assured.   All trails were groomed Thursday for Skate and Classic except Sheep Thrills, which is scheduled for a Friday compaction and groom.