The assistant ski guide exam just finished a week of ski touring based in Lake Louise (March 24-30). We did day trips from Chickadee Valley to Bow Summit and spent 3 days assaulting the Wapta from all directions.
The beginning of the week saw mild temps (+5 in the alpine) and up to 40 cms of snow accompanied moderate west winds. As a result we saw avalanche activity size 2-3, often triggered by cornice fall.
Starting on the 26th we saw the beginnings of a melt-freeze cycle and by the end of the week this was in full swing with diurnal temperature swings from -15 to +5. Isolated avalanche activity continued on NE aspects, nearly always associated with cornice triggers, with slabs propagating in steep cliffy terrain and fans. On solar aspects there were wet loose snow avalanches during the warm part of the day.
By the end of the week we felt that avalanche danger varied with solar aspects becoming becoming unstable with daytime warming and cornices being susceptible to slight triggers such as warming from the morning sun.
Travel conditions were good on crusts and low ski pen in sheltered areas. Good powder skiing could be found on protected N aspects, and also on steep solar aspects where the crusts were supportive.
Mark Klassen Mountain Guide |