Subject: April 4, 2005 Canadian Avalanche Centre PAF

North Columbia Region
Forecast of avalanche danger beginning Monday, April 4, 2005:

Day:\Monday p.m.\Tuesday\Wednesday
Alpine:\Considerable\Considerable\Considerable
Treeline:\Considerable\Considerable\Considerable
Below Treeline:\Moderate\Moderate\Moderate

Travel Advisory: A number people buried by avalanches last week, very
large avalanches on the weekend and tricky snowpack conditions are Mother
Nature^Òs hints to ease off the throttle. Areas above 2400 m (8000 ft)
elevation should be considered suspect and high marking should be avoided
in these areas. Be suspicious of steep, wind-loaded bowls, gullies and
areas below ridgelines, especially areas with cornices hanging over them.

Avalanches: A significant natural avalanche cycle was reported early this
weekend in the northern parts of the Monashee and Cariboo ranges. Some of
these were large, up to Size 3, or big enough to bury a car. Just south of
our region northeast of Lumby, an avalanche took the life of a
snowmobiler, but we currently have few details.

Snowpack: The snowpack is complicated right now, so I^Òll try to keep
things simple. There is 50-120 cm of snow sitting on top of a hard crust
which we call the March 16th crust. Within this snow, there are a number
of weak layers that are popping out in stability tests and ski cuts; some
pop out easily and some out hard. Some areas report weak facet crystals
sitting on top of the crust which forms a very weak layer responsible for
many of the large avalanches observed this weekend. Don^Òt underestimate
the ability for even a small avalanche to step down to this deeper weak
layer, resulting in an unexpectedly large avalanche.

Weather: A Pacific storm will send a disturbance across the BC Interior on
Tuesday and Wednesday. This is expected to be primarily a wind event
except in the northern parts of the region where 10-20 cm of snow could
materialize at higher elevations. Mountain winds should ramp up from the
south or southwest Tuesday, with snowfall above 1500 m late in the day and
overnight Wednesday.

issued by is, aj