In partnership with: Utah Division of State
Parks and Recreation, The Friends of the Utah Avalanche Center, Utah Department
of Emergency Services and Homeland Security and
“keeping
you on top”
AVALANCHE ADVISORY
Tuesday,
January 08, 2008 7:30 am
Good morning, this is Brett Kobernik with
the
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Current Conditions:
Under
partly cloudy skies, temperatures again plummeted to the single digits at most
mountain locations. Winds are light from
a westerly direction. Yesterday
afternoon’s weather disturbance produced a few inches of snow in the
Cottonwoods, Park City Ridgeline and
Avalanche Discussion:
Control results
continued to produce deep slab avalanches at the ski resorts on Monday. One of our observers experienced a large
collapse in the East Bowl of Silver Fork however no avalanche released. It sounds like the failure was into older
faceted snow. Also, a group produced a
massive avalanche in upper north facing Days Fork after dropping a few
cornices. The second large cornice
triggered an avalanche around 3 feet deep and 500 to possibly over 1000 feet
wide. This bent over trees and
completely covered the runout zone below.
This avalanche ran over an area that many people consider to be out of
the way where they regroup at the bottom of the slope. It also took out the area where an up-track
is being used more and more. This area
has avalanched earlier in the season making this a repeater slide. Go to our photos page for some images.
I’d like to point out
a couple of things here to take into consideration. This is the site of countless close calls and
accidents including fatalities. However,
people get complacent with this area because of its ease of access and the frequency
it gets skied. The up track that is
constantly put in is not in a safe area.
Many people stand directly in the run out zone at the bottom of this
slope which is not safe either. In my
opinion, it is just chance that this slope wasn’t littered with people skiing,
climbing and standing at the bottom when the slide ran. At least one observer considered skiing this slope yesterday and it’s my bet he wasn’t alone
with this thought.
For today, the biggest
concern is deep slab avalanches. These
are not hair trigger. There are no
obvious signs of instability aside from examining the weak layers in the
snowpack. I don’t think stability tests
on these weak layers are worth much with these conditions. Unless you are an expert at identifying weak
layers and determining slab strength over these weak layers while taking into
account spatial variability, you have no business being on these steep
slopes. Steep slopes just outside of the
ski area boundaries are not exempt. On
the north facing slopes, faceted snow from October is the problem. On east, west and south facing slopes, snow
from late November and early December has become faceted especially in areas
that were previously shallow. There is
now a significant slab over this junk which we must pay attention to.
Bottom Line for the
The
avalanche danger is MODERATE for deep slab avalanches. These are possible on a variety of aspects
and mainly above around 8500 or 9000 feet in elevation. Safe travel protocol needs to be followed as
consequences may be severe. Keep in mind
the avalanche danger will be on the rise later today into Wednesday.
Mountain Weather:
We’ll see partly
cloudy skies with increasing clouds as the next storm system moves in. Ridgetop temperatures will climb into the
teens and low 20s with southwest winds increasing through the day. Westerly flow will produce a foot or so of
snow tonight into Wednesday for much of the
Announcements
The Wasatch Powderbird Guides were in American Fork canyon on Monday and will
be in
Solitude’s beacon park is now up and running, and ready for use. It’s FREE and located just off the northwest
corner of the lower lot.
For an avalanche education class list,
updated 12/22/07, click HERE.
If you want to get this avalanche advisory e-mailed to you daily click HERE.
UDOT highway avalanche control work info can be
found HERE or by calling (801)
975-4838.
Our statewide tollfree line is 1-888-999-4019 (early morning, option 8).
For our classic text advisory click HERE.
If you’re getting out and see anything we should know about please let us know. You can leave a message at (801) 524-5304 or
1-800-662-4140, or email us at [email protected]. (Fax 801-524-6301).
The
information in this advisory is from the U.S. Forest Service, which is solely
responsible for its content. This
advisory describes general avalanche conditions and local variations always
occur.