Banff, Yoho and Kootenay National Parks

Issued:
 Tuesday, January 13, 2009   18:39
Valid Until:
 Wednesday, January 14, 2009   
Bulletin Area:
 This forecast covers the east and west sides of the Continental Divide from the 
 Wapta Icefields area in the north to the Sunshine area in the south. It also 
 includes the Main Range area from Lake Louise to Bow Summit.

Parks Canada strongly recommends that the general public avoid areas where the 
avalanche danger rating is HIGH or EXTREME. Any travel in these areas should be 
restricted to Simple terrain or kept within the boundaries of a ski resort.

Danger Rating:
				Tuesday 		Wednesday 		Thursday 	
Alpine 			4-High 			3-Considerable 	3-Considerable
Treeline 		3-Considerable 	3-Considerable 	3-Considerable
Below Treeline 	3-Considerable 	3-Considerable 	3-Considerable


Synopsis:

 A significant winter storm, ending January 8th, dumped 60-70 cm of snow at treeline 
 along the continental divide. Strong winds after the storm have created wind slabs 
 at all elevations that are very susceptible to skier triggering. To exasperate the 
 problem the storm snow and wind slabs are sitting on a very weak facet layer that 
 is about 50 cm below the surface.

The wind slabs and the weak facet layer that the storm snow is sitting on was responsible 
for a wide spread avalanche cycle during and just after the storm. Although the natural 
cycle is over there have been reports of skier triggered avalanches up until today. Any 
slope that has not avalanched should be considered suspect.

Due to the nature of the weak facets under the storm snow this instability will persist 
for some time into the future. Now is the time for conservative terrain choices while 
enjoying the fresh powder in the back country. bw

Avalanche Activity:

 Although the natural avalanche cycle is over there have been reports of skier triggered 
 avalanches up until today. Any slope that has not avalanched should be considered suspect.

Outlook:

 No significant snow is expected in the near future. Thursday looks like it will be sunny 
 and clear. Don't get sucked into the trap that a sunny day brings good stability. The weak 
 facetted interface that sits below the storm snow will be a problem for some time into the 
 future.

The forecast calls for freezing levels to be above 2500 metres by the weekend. If this 
happens the avalanche danger will rise considerably. There is a chance that these warm 
temperatures will arrive sooner then forecasted, so be aware of rising freezing levels 
toward the end of the week.

Travel Conditions:

 The storm snow has started to settle and the ski penetration is now between 20 and 25 cm.