April 13, 2002

Canadian Avalanche Association Bulletin

ROCKIES REGION

WEATHER: After some warm but wet weather last week, the BC Interior spit out
a cold front that affected primarily the Fernie area early in the weekend,
although weather forecasters predict it will spread throughout the region
Saturday night and Sunday morning. Heavy moisture will occur as the front
cools the airmass, resulting in rain at low elevations and snow in the
alpine. Generally cool and unsettled weather will follow.
SNOWPACK: Much of the Rockies snowpack is very near isothermal. Saturday's
rain will drive the low elevation snowpack into full isothermal conditions,
with very little strength remaining. In the alpine, the heavy snow load is
expected to begin to overload mid snowpack strengths, leading to deep
instabilities such as the November crust coming alive with a vengeance.
AVALANCHES: Near Fernie, reliable results to size 2 were being reported from
explosive control work at low and mid elevations, running wet and loose.
Near Japer, naturals to size 3 were observed failing to the November crust,
one of which involved an entire bowl.
FORECAST OF AVALANCHE DANGER UP TO MONDAY EVENING (April 15)
ALPINE - Considerable, areas of High. Improving slightly with cooling
TREELINE - Considerable, improving slightly with cooling
BELOW TREELINE - Considerable
TRAVEL ADVISORY: The November crust is back to stay. We may see some reduced
avalanche activity from lingering cool air in the wake of the cold front,
but the time has come to carefully assess each route with the thought in the
back of your mind, "What if I'm wrong and the whole bowl goes?"  Pick your
terrain accordingly.