The Canadian Avalanche Centre's bulletin for Whistler has downgraded the avalanche hazard for the Whistler Blackcomb backcountry area to "Considerable" today (Sunday, March 18), where it will remain through Tuesday. The hazard at treeline and below tree line is currently "Moderate" but will go back to Considerable on Tuesday when another system will arrive bringing heavy snow and higher winds.
That doesn't mean there is no risk. At Considerable the Avalanche Danger Scale warns of "Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential. Natural avalanches possile; human-triggered avalanches likely." Moderate means "Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern."
With over two metres of snow falling the previous week, the hazard went up to "High" on Friday, which means natural avalanches were likely and human-triggered avalanches very likely, and travel in the backcountry is not recommended.
A special avalanche bulletin was published on Friday for the interior of the province extending as far as Pemberton. That bulletin was to remain in effect until Monday when avalanche hazard would be re-evaluated.
The special bulletin is the result of heavy snow and high winds, and the possibility of deep weaknesses in the snowpack letting go. With periods of sun and improving weather the concern was that a lot of people would head out to enjoy the new snow and sunshine and put themselves at risk.