Northwest - BC Avalanche Forecast

Date/Time issued: Friday, March 30, 2007 at 3:00 PM
Valid until: Monday, April 02, 2007

Forecast of avalanche danger 
 	            Friday	        Saturday	    Sunday	        Monday
Alpine	        Considerable	Considerable	Considerable	Moderate
Treeline	    Considerable	Considerable	Moderate	    Low
Below Treeline	Considerable	Moderate	    Low	            Low

There are large variations in how the storm affected areas throughout the region. 
Avalanche danger ratings are based on more than 30 to 40 cm of precipitation by 
Friday morning and minimal precipitation after that. Avalanche danger may be 
lower in inland areas where the storm was less intense.

Travel Advisory:  Watch for rising temperatures and increasing wind the next few 
days; either are likely to get avalanches rolling again. If you're in an area with 
deep, cold, powdery snow even moderate winds could quickly re-load slopes with 
fat sensitive slabs. If the temperature spikes rapidly, all the cold new snow 
near the surface could settle into a cohesive slab faster than the layers below - 
a recipe for instability and avalanches. Regardless of the weather, avoid exposure 
to the runouts of slopes overhung by large cornices.

It's a good idea to start with simple and even low angled terrain when you first 
head out. Make field observations to figure out how much new snow there is, how 
it was affected by the wind, and whether it's bonding to the layers below. Whumpfing, 
cracking, or hollow snow sounds are signs of unstable snow and mean it's time of back off.

Avalanche Activity:  In high snowfall areas near the coast the mountains rumbled 
with an impressive widespread dry and wet snow avalanche cycle to size 3.5 running 
to valley floors. Inland areas reported small controlled and accidentally triggered 
avalanches.

Snowpack:  Storm snow reports vary from 100 cm near Terrace and Stewart, 40 cm near 
Ningunsaw and west of Smithers, to 20 cm on Hudson Bay Mtn. This was a major winter 
storm very late in the season. The snow appears to be settling and strengthening 
rapidly with a few concerns reported: reactive at lower elevations where it rests on 
smooth hard crusts, reactive in wind loaded areas, and cornice growth is impressive. 
There's lots of snow available for transport and it'll take a few days before the 
snowpack finds a new equilibrium and avalanche danger declines.

Weather:  The stalled front started moving overnight Thursday bringing an end to 
the winter storm. Precipitation varied throughout the region (for example Terrace 
received 53 mm of precipitation Thursday while Smithers received 2 mm). Through 
Monday the region should see diminishing SW winds, a mix of sun & clouds, scattered 
light precipitation, and freezing temperatures near 700 m. Warmer, drier, sunnier 
weather likely returns on Tuesday.

Issued by: ilya storm