The Truckee Police Department and the Truckee Fire Protection District have noticed the recent surge in popularity of ice-skating on Donner Lake. This is worrisome, authorities said, because while conditions in the past month have been extremely cold, the current conditions have warmed considerably and the ice is generally unstable. Northern California generally does not have the consistently cold temperatures to sustain ice on area lakes and ponds due to their size and water currents. The conditions present today on Donner Lake are similar to conditions five years ago, when a skater fell through the ice and drowned. Ice that …