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
Sunday,
January 06, 2008 7:30 am
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Current Conditions:
It’ll be
old news soon, but it’ll be awhile before I forget yesterday’s storm. Let’s look at the numbers: Little Cottonwood
17”/4” h20, Big Cottonwood 21”/4.56”h20,
The next
storm is already upon us with snow falling again in the mountains. Winds have shifted to the southwest and are
blowing 25-30mph with gusts into the 40’s.
Temperatures have warmed with the warm front and are in the upper teens
and low twenties.
Avalanche Discussion:
It’s likely that we experienced
a widespread shallow natural cycle with the explosive water numbers yesterday,
but poor visibility and immediate reloading precluded much in the way of data
and observation. There were, however,
some important events in the backcountry, representing our increasingly varied
snowpack. A large full depth natural
reportedly broke out ‘wall to wall’ in what’s fondly known as ‘Radar Love Bowl’,
just south of Scott Peak along the Park City ridgeline. It’s a steep east facing slope at about 9800’. Just around the bend there in upper
In 1971, Wallace Stegner wrote an American classic called Angle of Repose. While I think the title refers to a person’s
place in life, in snow anyway it has to do with the angle in which snow can
sufficiently stick to the slope before falling away. Graupel, the crystal type that made up the
bulk of yesterday’s storm, is notorious for having a low angle of repose, the
simple explanation on why many avalanches running on the ball bearings are on
lower angled slopes or at the base of cliffs where they’ve bounced down and
congregated. They’re famous for being
loose and unconsolidated and we’re likely to see more activity on this layer
for the next few days.
Anytime you hammer the
snowpack with this explosive amount of water weight, you’re likely to see large
and unusual avalanches. Snow and the
shear strength between the various layers is such a dynamic, ever-changing
environment. And so it was to everyone’s
surprise to see a large natural 4’ deep and 150’ wide pull out overnight
inbounds in semi-compacted terrain in the lower mid cirque in mid-Big
Bottom Line for the
In areas
that received the most snow, the avalanche danger is CONSIDERABLE on all slopes 35 degrees and
steeper. Human triggered avalanches may
continue to be up to 4-5’ deep in overloaded terrain.
Mountain Weather:
We’ll see
snow throughout the day with this current system with heavy snowfall rates with
frontal passage in the early afternoon.
The
Announcements
Wasatch Powderbird Guides did not fly yesterday, and will not be flying today
due to high winds. For more information,
call them at 801-742-2800.
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.
I
will update this advisory by 7:30 on Monday morning.