----------------------------------------------------------------
  INSTITUTE FOR SNOW AND AVALANCHE RESEARCH  DAVOS
               NATIONAL AVALANCHE BULLETIN NO. 116
           from Friday, 23 March 2007, 18:30 hours
----------------------------------------------------------------
  PARTICULARLY IN THE NORTH CONSIDERABLE AVALANCHE DANGER
----------------------------------------------------------------


CURRENT CONDITIONS

On Friday it was partially bright in the south, elsewhere it was 
overcast with intensely diffuse radiation. Along the northern 
flank of the Alps, 15 to 30 cm of loosely packed snow has fallen 
since Thursday evening, in the southern bordering areas, about 5 
to 10 cm. On Friday, light to moderate westerly winds prevailed. 
Midday temperatures at 2000 m were minus 8 degrees in the north 
and minus 5 degrees in the south. 
Since Tuesday along the northern flank of the Alps and in Val de 
Bagnes, widespread 30 to 50 cm of snow has fallen. In the region 
of Hasliberg and from central Switzerland to Walensee, 90 cm of 
new snow fell, in the southern bordering areas, 10 to 30 cm. The 
fresh snow is loosely packed and usually well bonded with the 
old snow. In exposed places there are treacherous snowdrift 
accumulations which are sometimes difficult to recognize. 
Particularly in inneralpine regions, the weak snowpack fundament 
is prone to triggering in some places.


SHORT-TERM DEVELOPMENT

On Saturday in the Valais and the Ticino it will initially be 
still pleasant. In the north and in Grisons, it will be overcast 
and up to 10 cm of snow will fall. The midday temperature at 
2000 m will be about minus 6 degrees. Weak bise winds will 
prevail. The fresh snow of recent days will continue to 
consolidate.


AVALANCHE DANGER FORECAST FOR SATURDAY

The northern flank of the Alps; western and northern Lower 
Valais; northern Tavetsch; northern Surselva; northern 
Grisons; Upper Engadine and Bergell:
  Considerable Avalanche Danger (Level 3)
In the northern Prealpes, in the central part of the northern 
flank of the Alps not including Urseren, as well as in the 
eastern part of the northern flank of the Alps and in 
northern Praettigau, the avalanche prone locations are on 
steep slopes in all aspects above approximately 1600 m. In 
the Upper Engadine and in Bergell, the avalanche prone 
locations are primarily on snowdrift slopes in all aspects 
above approximately 2300 m. In all other regions of this 
danger level, the avalanche prone locations are on steep 
slopes in all aspects above approximately 2000 m. 
Snowdrift accumulations are critical and often difficult to 
recognize. Experience in the assessment of avalanche danger 
and careful route planning are essential.

The remaining Valais; northern and central Ticino; the remaining 
areas of Grisons:
  Moderate Avalanche Danger (Level 2)
The avalanche prone locations are on steep slopes in all 
aspects above approximately 2000 m. The fresh snowdrift can 
easily be triggered, although the amounts of released snow 
are usually small. Particularly in inneralpine areas, 
isolated fractures down to the old snow cover are possible.

Especially in the north, snow slides on the ground down into low 
lying altitude zones are possible.


TREND FOR SUNDAY AND MONDAY

It will turn sunny and somewhat warmer. The avalanche danger 
will slowly diminish. On steep sunny slopes and in lower lying 
altitude zones, moist snow slides and avalanches can be 
expected.