This is Tony Willits with the backcountry avalanche advisory issued by
   the U.S. Forest Service Glacier Country Avalanche Center at 8:00 AM,
   Tuesday, February 27th for the Glacier Park and Flathead and Kootenai
   National Forest areas.
   
   HAZARD ANALYSIS
   
   The avalanche danger between 5,500 and 7,500 ft. elevation is
   currently being rated as CONSIDERABLE, on terrain that recently
   received significant amounts of  precipitated  snow.  On other slopes
   with lesser snowfall amounts, between 5,500 and 7,500 ft. elevation
   the hazard is rated as MODERATE. Below 5,500 ft. elevation the danger
   is rated LOW.
   
   These danger ratings expire at midnight, Tuesday, February 27th.  The
   outlook is for the avalanche danger to remain near current levels
   through Thursday.
   
   Because of the general nature of this advisory message, each
   backcountry party will always need to make their own time and site
   specific avalanche hazard evaluations.
   
   WEATHER ANALYSIS:
   
   Mountain temperatures were on the warm side when the last snow was
   delivered overnight Sunday and during the day Monday.  Then
   temperatures crept downward and a bit into the teens overnight at
   upper elevations.  Snow falling yesterday came in spurts across the
   region and was variable in accumulation amounts with the Cabinents
   receiving .2 to .4 of an inch of snow water equivalent (SWE) and the
   Southern Whitefish Divide and the west side of the Park receiving .5
   to .6 of an inch of SWE.  The Northern Swan and Mission Ranges were
   healthier yet with the Noisy area receiving 1.5 inches of SWE.  Winds
   were  a little gusty until midday on Monday in the Northern Swan with
   wind speeds from 10 to 12 mph.   As  well, winds speeds in the Middle
   Fork Corridor were on the light side in the valley bottom along the
   highway with no recordings available at the upper elevations.

   SNOWPACK ANALYSIS:
   
   Our backcountry observations Monday were from Noisy Basin on the
   Flathead National Forest.  Please see the GCAC website for Regional
   Observations posted Sunday.
   
   Noisy Basin had a fair amount surface instabilities with triggered 4
   to 6 inch fractures occurring on steep cut slopes.  Natural and
   triggered releases were observed. East facing slide paths were
   triggered with 8 inch fractures and running to the bottom of the
   paths.  A natural release was observed that zippered across the lower
   two thirds of a slope pulling out to a depth of 1 foot and running to
   the moraine below.  Did not note any west facing slopes releasing
   although visibility was limited.   The weak interface seemed to be
   some well preserved needles falling at the beginning of the
   disturbance.  The surface 50 cms above the first most prominent ice
   layer was where most stress failure were occurring.  Below the bed
   surface of yesterday's activity hard forces were required although all
   were clean snappy shears.  Multiple melt freeze ice layers below the
   surface 50 cms are bridging over varying hardness layers of old facets
   that are in varying stage of rounding.

   AVALANCHE - INSTABILITY DESCRIPTION:

   We're currently rating the avalanche danger as CONSIDERABLE on slopes
   between the elevations of 5,500 and 7,500' that recently received
   significant deposits of  precipitated snow. Unstable loose snow as
   well as unstable surface and near surface slab layers are probable on
   steep terrain. Natural avalanches are possible, while human triggered
   avalanches are probable. Backcountry travelers should be very cautious
   in steeper terrain. Be aware of potentially dangerous areas of
   unstable snow.

   Between 5,500 and 7,500' elevation on slopes that have not received
   recently significant deposits of new snow, the avalanche danger is
   rated as MODERATE. Unstable surface slab layers atop melt-freeze ice
   are possible there. Natural avalanches are unlikely, but human
   triggered avalanches are possible. Backcountry travelers should use
   caution in steep, open terrain on all aspects.

   Below 5,500 ft. elevation we're rating the avalanche danger as LOW.
   The more shallow snow there is often anchored by vegetation and
   terrain features and generally stable with only isolated areas of
   instability. Natural avalanches are very unlikely, while human
   triggered avalanches are unlikely. Backcountry travel is generally
   safe, but normal caution is still advised.
   
   WEATHER FORECAST & AVALANCHE OUTLOOK:
   
   A vigorous weather system will move across Westcentral and Southwest
   Montana Tuesday.  A cold upper trough of low pressure and associated
   cold moist and unstable atmosphere will persist Wednesday and
   Thursday.
   
   The expectation is for more disturbances to move across our area for
   the next several days.  Expect the hazard to stay at the current
   levels especially with additional loading.

   Please note that this avalanche advisory is our best interpretation of
   snow pack conditions and National Weather Service forecasts on the day
   the advisory is issued. Unanticipated weather changes such as wind, a
   marked temperature increase, or precipitation beyond forecast amounts
   can increase the avalanche danger. Local variations may also exist.
   The next avalanche advisory will be on Friday, March 2, 2007.