Spring, 2001

This Bulletin Sponsored by Canadian Avalanche Foundation

NOTICE OF UNUSUAL AVALANCHE CONDITIONS:  Valid until further notice.

This season avalanche professionals between the Inner Coast Mountains and
the Rocky Mountains have observed snowpacks that are unusually weak.  The
combination of below normal snow depth and low temperatures has produced
layers of facetted grains and surface hoar with a low strength.  These types
of weak layers can persist for a long time, and the avalanche danger will
increase with every load of new snow onto this weak base.

The present snowpack is less stable than in most other years and remarkably
different from the snowpack at the same time last winter.  Back country
users will have to pay much attention to snowpack structure and strength
during this winter.

SOUTH COAST REGION

WEATHER: The classic spring pattern is now fully underway, with periods of
warm weather mixed with some generally unstable airmass activity, leading to
good old April showers. Rain has now been reported to treeline, although
some new snow is certainly still arriving at high elevations during some of
these stormy periods. When the sun does come out, it packs a punch,
transferring energy into the upper snowpack layers very rapidly.
SNOWPACK: The snowpack is now under the influence of the change in seasons,
leading to a general rise in snowpack temperatures, as the spring melt gets
underway. As the snowpack warms, this tends to eliminate the difference
within layers within the snowpack. Eventually, the heating causes the snow
to reach zero degrees, a point where the snow looses all strength just
before it turns to free water.
AVALANCHES: No recent reports of deep instabilities have been submitted,
although the flow of information from observers is already very reduced as
operations close for the season. Frequent small surface slides during
storms, or wet loose slides in direct sun are common right now. The overall
trend will be for the best stability to be found in the cool mornings, with
a deterioration throughout the day as warming affects the snowpack.
AVALANCHE DANGER	ALPINE ^Ö Generally Moderate, increasing in the afternoons
                  TREELINE ^Ö Generally Moderate, increasing in the
afternoons
                  BELOW TREELINE - Generally Moderate
TRAVEL ADVISORY: Ever wonder who is out there every day snow or sun,
collecting data to help put this bulletin together? In this region, it^Òs
Blackcomb Resort, Whistler Resort, Whistler Heliskiing, Cayoosh Helisports,
TLH Heliskiing, and BC Ministry of Transport and Highways Duffy Lake and
Coquihalla. Thanks for helping!

NORTH COLUMBIA REGION

WEATHER: The classic spring pattern is now fully underway, with periods of
warm weather mixed with some generally unstable airmass activity, leading to
good old April showers. Rain has now been reported to treeline, although
some new snow is certainly still arriving at high elevations during some of
these stormy periods. When the sun does come out, it packs a punch,
transferring energy into the upper snowpack layers very rapidly.
SNOWPACK: The snowpack is now under the influence of the change in seasons,
leading to a general rise in snowpack temperatures, as the spring melt gets
underway. As the snowpack warms, this tends to eliminate the difference
within layers within the snowpack. Eventually, the heating causes the snow
to reach zero degrees, a point where the snow looses all strength just
before it turns to free water.
AVALANCHES: No recent reports of deep instabilities have been submitted,
although the flow of information from observers is already very reduced as
operations close for the season. Frequent small surface slides during
storms, or wet loose slides in direct sun are common right now. The overall
trend will be for the best stability to be found in the cool mornings, with
a deterioration throughout the day as warming affects the snowpack.
AVALANCHE DANGER	ALPINE ^Ö Generally Moderate, increasing in the afternoons
                  TREELINE ^Ö Generally Moderate, increasing in the
afternoons
                  BELOW TREELINE - Generally Moderate
TRAVEL ADVISORY: Who takes the daily readings for this zone? It^Òs done
faithfully by Mike Weigele Heliskiing, Crescent Spur Heliskiing, Robson
HeliMagic, Canadian Mountain Holidays McBride, Valemount, Caribous,
Monashees, Gothics, Adamants, and Revelstoke, BC Ministry of Transportation
and Highways Revelstoke, Selkirk Tangiers Heliskiing, Glacier National Park,
and Cat Powder. Thanks for helping!

SOUTH COLUMBIA REGION

WEATHER: The classic spring pattern is now fully underway, with periods of
warm weather mixed with some generally unstable airmass activity, leading to
good old April showers. Rain has now been reported to treeline, although
some new snow is certainly still arriving at high elevations during some of
these stormy periods. When the sun does come out, it packs a punch,
transferring energy into the upper snowpack layers very rapidly.
SNOWPACK: The snowpack is now under the influence of the change in seasons,
leading to a general rise in snowpack temperatures, as the spring melt gets
underway. As the snowpack warms, this tends to eliminate the difference
within layers within the snowpack. Eventually, the heating causes the snow
to reach zero degrees, a point where the snow looses all strength just
before it turns to free water.
AVALANCHES: Some reports of avalanches failing to or stepping down to the
November facet layer have been submitted, although the flow of information
from observers is already very reduced as operations close for the season.
These failures generally involve the entire season snowpack, so avalanches
up to size 3.5 have recently been reported. The overall trend will be for
the best stability to be found in the cool mornings, with a deterioration
throughout the day as warming affects the snowpack.
AVALANCHE DANGER	ALPINE ^Ö Generally Considerable  increasing in the
afternoons
                  TREELINE ^Ö Generally Moderate, increasing in the
afternoons
                  BELOW TREELINE - Generally Moderate
TRAVEL ADVISORY: Ever wonder who helps develop this bulletin by taking the
field readings. You can thank Golden Alpine Holidays, Kicking Horse Resort,
Purcell Heliskiing, Great Canadian Heliskiing, Canadian Mountain Holidays
Bobbie Burns, Bugaboos, Galena, and Kootenay, RK Heliskiing, Panorama
Resort, Big White, Selkirk Wilderness Skiing, Kokanee Glacier
Mountaineering, Sun Peaks Resort, Silver Star Resort, and BC Ministry of
Highways Central Region, Kootenay Region, and Kootenay Pass. Thanks for
helping!

ROCKIES REGION

WEATHER: The classic spring pattern is now fully underway, with periods of
warm weather mixed with some generally unstable airmass activity, leading to
good old April showers. Rain has now been reported to treeline, although
some new snow is certainly still arriving at high elevations during some of
these stormy periods. When the sun does come out, it packs a punch,
transferring energy into the upper snowpack layers very rapidly.
SNOWPACK: The snowpack is now under the influence of the change in seasons,
leading to a general rise in snowpack temperatures, as the spring melt gets
underway. As the snowpack warms, this tends to eliminate the difference
within layers within the snowpack. Eventually, the heating causes the snow
to reach zero degrees, a point where the snow looses all strength just
before it turns to free water.
AVALANCHES: Some reports of avalanches failing to or stepping down to the
November facet layer have been submitted, although the flow of information
from observers is already very reduced as operations close for the season.
These failures generally involve the entire season snowpack, so avalanches
up to size 3.5 have recently been reported. The overall trend will be for
the best stability to be found in the cool mornings, with a deterioration
throughout the day as warming affects the snowpack.
AVALANCHE DANGER	ALPINE ^Ö Generally Considerable  increasing in the
afternoons
                  TREELINE ^Ö Generally Moderate, increasing in the
afternoons
                  BELOW TREELINE - Generally Moderate
TRAVEL ADVISORY: Ever wonder who volunteers the observations that go into
putting together this bulletin? This winter, Marmot Basin Resort, Jasper
Warden Service, Banff Warden Service, Yoho Warden Service, Kootenay Warden
Service, Skiing Louise, Sunshine Resort, Mt Norquay, Kananaskis Park, Island
Lake Cat Skiing, Fernie Alpine Resort, and Waterton Lakes Warden Service
deserve a well earned thank you for being out there taking readings on a
daily basis all winter long.