Avalanche Forecast - South Rockies   
Date Issued   Thursday, 08 March 2012 5:33 PM   	   	
Valid Until    Friday, 09 March 2012 4:00 PM

Public Avalanche Forecast

Note: This covers Friday, the day of an incident with one fatality. The Danger Rating for Saturday
      and Sunday was elevated to HIGH. There was reportedly a warming trend in progress.

Friday Danger Rating:   
Alpine, Treeline, Below Treeline- 3 - Considerable - 
  
   Dangerous avalanche conditions. Careful snowpack evaluation, cautious route finding and 
   conservative decision making essential.

Wind Slabs - Recent SW and NW winds have set up touchy wind slabs in lee terrain in exposed areas.

Storm Slabs - New snow has generally bonded well to existing snow surfaces. However, places to 
              watch are steep rolls and unsupported, convex slopes.

Persistent Slabs - A prominent persistent weak layer from the middle of February exists in some 
                   areas, and is most prevalent in the Flathead range. If triggered, this layer has 
				   the potential to produce large and dangerous avalanches.

Travel and Terrain Advice

    Be aware of the potential for full depth avalanches due to deeply buried weak layers.
    Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.
    Remote triggering is a concern, watch out for adjacent slopes.
    Avoid open slopes and convex rolls at and below treeline where buried surface hoar 
	    may be preserved.
    Do not travel on slopes that are exposed to cornices overhead.
	
Avalanche Summary

On Wednesday, a size 2 avalanche was reported from around 2300m in the South York Creek area on an 
east aspect. Limited amounts of sluffing from solar activity was also noted. On Tuesday a snowmobiler 
was buried in an avalanche below treeline in the Flathead.

Snowpack Summary

20 to 50 cm of recent storm snow has been reported from different parts of this region. Winds from 
the SW and the NW have set up wind slabs in lee areas in exposed terrain. Warm temperatures have 
moistened the snow surface in many locations; where this has happened, expect an overnight freeze to 
set up a surface crust. The mid February surface hoar layer is now down between 40 & 100cm and is 
more prevalent in the west and south of the region, particularly in the Flathead. Recent snowpack 
tests as well as a rider-triggered avalanche on this weak layer indicate that it still has the 
potential to be triggered in many areas and if it is triggered, a large avalanche could result. 
Lingering concern remains for basal facets, particularly in shallower snowpack areas with steep, 
rocky start zones. Cornices are becoming well developed in response to recent winds and are likely 
starting to droop with the warm temperatures.

Weather Forecast

Another dry day is expected for Friday. Freezing level is expected to remain high at around 2300 m 
and strong southwesterly winds are anticipated. For Saturday, flurries or light rain is expected, 
with only minimal accumulation. Winds should be moderate southwesterly and freezing levels should 
drop to around 1800 m. On Sunday, further light snow/rain is expected with continued southwesterly 
winds and freezing levels around 1700 m.