Avalanche Observation : February 11, 2010
Date:
February 11, 2010 Observation Type:
Snowpit / Stability Observation
Route:
Up Tobacco Flat, up Old Man Bowl, down then up to Morrison Col and down the North Bowl to Convict Lake
Weather:
Initially cool, but rapid warming with significant solar input
Avalanche Activity:
Older loose slides from the weekend/Tuesday snow but then with heat input increasing activity of loose wet snowballs and instabilities in the upper layers.
Snow started out great dry powder up out of Convict Lake. Skiing in Old Man Bowl was great with some 30cm of dry powder. The climb up into Morrison Col had seen significant wind action and much snow had been stripped and then the sun had removed even more. Coverage is thin and down skiing this would not be a good option. Some evidence of older slides from the south facing slopes of Little Morrison. At the Col there is a small cornice with about 2.75 meters of snow below this. We had concerns about slabs here but nothing was in evidence and things seems well bonded. As we dropped the snow became increasingly more dense with 10-15cm of lighter snow on top of a firm hard layer on the final 1000 feet to the Lake. By the time we got to the Lake there was plenty of evidence of small loose wet avalanches moving on top of this firmer layer even on north facing slopes that had seen little sun. We hit this at 3.30pm and maximum instability. Choices around the Lake are to deal with the upper layer instabilities, cross the Lake with obvious open water spots or deal with crossing Convict Creek and no good bridges. We opted to deal with the snow! Pick your poison and drink it...... Most importantly the bar at the Convict Lake Restaurant is open.