Kootenay Boundary Avalanche Forecast

Date Issued:   Friday, January 04, 2008 at 6:00 PM
Valid Until:   Sunday, January 06, 2008

Forecast of avalanche danger 
  	              Saturday 	    Sunday 	     Monday
Alpine 	             HIGH 	 CONSIDERABLE 	CONSIDERABLE
Treeline 	    CONSIDERABLE 	MODERATE 	MODERATE
Below Treeline 	   MODERATE 	MODERATE 	MODERATE

Travel Advisory   

Finally, it is your turn my friends. Ground zero for snowfall in the BC Interior is the 
Kootenays through Saturday. There are three concerns in the snowpack, which will have you 
tip toeing around or waiting for more stable conditions. The first is windslabs. Heavy 
snow and wind are building them up. On Saturday, they should be relatively to trigger in 
steep terrain. Don’t underestimate them. The second concern is a weak layer buried well 
over 100cm deep. Most circles of people refer to this as the Dec 5 crust. With 20 cm of 
snow overnight Thursday, and an additional 20-40cm expected through Saturday, the Dec 5 
layer may awaken. Travel away from steep and open slopes. Third is shallow snowpack areas 
are incredibly weak consisting of sugar snow. You may find these areas where wind souring 
occurs.

Avalanche Activity   

Natural avalanche activity will likely peak in the early morning hours Saturday. Natural 
avalanche activity should taper off through Saturday, but continued winds and freshly built 
wind slabs should be ripe for triggering. Triggering a large avalanche on the December 5 layer 
is a concern this weekend. Remember these avalanches may be large and break well above you, once 
you are committed to the slope. This leaves very little chance to escape.

Snowpack   

The new snow is stacking up quickly. In addition to windslabs, look for storm snow instabilites. 
Also remember that the the Dec 5 weak layer buried 100cm to 160 cm deep, weak in places and being 
loaded fast.

Weather   

An impressive storm off the Oregon Coast is causing a strong warm moist flow over southeast BC 
on Friday. Freezing levels may reach 1400m on Friday before subsiding to 800m or lower on Saturday 
after a cold front passes. Above the freezing level, expect 25cm to 40cm of snow by Saturday 
morning. Moderate to strong flow at mid-elevations will cause gusty 30-50km/hr S or SW winds. 
Behind the front on Saturday, unstable air with westerly flow should produce 10-15 cm. 

Issued by:Greg Johnson