2 PM PST Friday 12 December 2003

ZONE AVALANCHE FORECASTS...

WASHINGTON CASCADES NEAR AND WEST OF THE CREST...
...AVALANCHE WATCH FOR SATURDAY...
Considerable avalanche danger above about 4000 feet and moderate 
below Friday. Avalanche danger increasing and becoming high above 
about 4000 feet and considerable below Saturday.

OUTLOOK TO SUNDAY...
Avalanche danger decreasing Sunday becoming considerable above 
about 4-5000 feet and moderate below in the Olympics and near and 
west of the Cascade crest. East of the crest expect a 
considerable avalanche danger above about 6000 feet and moderate 
below.

SNOWPACK ANALYSIS...
Periodic light snowfall and cool temperatures was generally seen 
the last few days. This lower density snow accumulated on higher 
density snow or a crust produced during a period of heavier 
precipitation and warmer temperatures the first week of December. 
No skier-released avalanches were reported to the NWAC for a few 
days ending Thursday. Older snow layers should have stabilized to 
some extent during that period. However the weather pattern and 
the avalanche potential began to change on Thursday night. About 
4-13 inches of new snow is reported on Friday morning in the 
Cascades near and west of the crest. This snow has fallen with 
moderate southwest to west winds along the ridge tops, east winds 
in the Cascade passes, and slightly warmer temperatures at higher 
elevations. This should have begun to cause a greater potential 
for slab layers on steeper lee slopes. Lower density snow and 
possible small hoar frost that may have developed early in the 
week during the occasional fair cool weather would contribute to 
this potential. Some initial natural 10 inch slab avalanches on 
35 degree north aspects were reported by the Mt Baker ski patrol 
on Friday morning. The best chance for new slab layers should be 
on north to east aspects at higher elevations and on more 
westerly aspects in the Cascade passes.

Saturday...
A strong front is expected to slowly cross the Olympics and 
Cascades on Saturday with the heaviest rain or snow in the south 
Cascades and Mt Hood area. This should be accompanied by 
increasing strong southwest winds along the ridge tops, warmer 
temperatures, a change from east to west winds in the Cascade 
passes, and moderate to heavy rain or snow especially in the 
south Cascades and Mt Hood area. The increasing density snowfall 
or possible rain depending on location should cause slab layers 
to develop Saturday on lee slopes. This should continue to be 
north to east slopes at higher elevations but on more varied 
aspects in the Cascade passes. Back country travel on or near 
steep avalanche terrain is not recommended with natural or 
triggered avalanches becoming likely Saturday.