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
Friday,
December 21, 2007 7:30 am
Good morning, this is Brett Kobernik with
the
I’ve continued the
avalanche warning through 6pm tonight. Strong winds over the last 24 hours coupled with more new snow has
elevated the avalanche danger to HIGH on many upper elevation steep
slopes. People without expert level snow
and avalanche assessment skills should avoid the backcountry today.
Little
Current Conditions:
It’s
officially a mess. A welcome mess but
nonetheless a mess. Take a good amount
of upside down snow, add strong winds with another good shot of snow overnight
and I think most people can do the math.
The floatation index yesterday morning was very low with most people
experiencing difficult trail breaking and difficult riding conditions making
them drool for larger tools to navigate through the snow. Winds gradually picked up during the morning
and really started drifting snow afternoon adding to the upside down feel to
the snow. Since the
passing of the front yesterday at around 5pm the Cottonwoods and Park City
Ridgeline picked up another 12 to 18” inches of lighter density snow. The Ogden area didn’t get as much but still received
around 6 inches and the Provo area received around 9 inches or a bit more. Clearing is currently happening in
Avalanche Discussion:
Natural avalanches
were reported from a number of locations in Little Cottonwood Canyon on
Thursday. There were human triggered
avalanches as well with at least one person getting caught, carried and
partially buried on the south facing slope about two thirds of the way up
Flagstaff in Little Cottonwood. There
were also a number of unintentionally triggered pockets in other areas of the
southerly facing slopes above the town of Alta as well as a slide in the West
Bowl of Silver Fork which was around 150 feet wide, 12 inches deep and ran
around 500 feet vertical. A skier
traversing a ridge near
It’s not worth
splitting hairs on the various weaknesses within the snow right now. Winds played a significant roll in drifting
the snow into sensitive slabs on many aspects Thursday afternoon. Some upper elevation north aspects may have
avalanched breaking into old snow. We
probably went through a natural avalanche cycle overnight which will be
subsiding this morning. However, many
slopes will be sensitive to the weight of a person still today. A number of savvy backcountry skiers I talked
to are not venturing into the backcountry today and will let the new snow
settle somewhat before poking around.
Bottom Line for the
The
avalanche danger remains HIGH on slopes approaching 35 degrees especially at the upper
elevations that were exposed to the winds.
The danger is CONSIDERABLE on slopes without recent wind deposits
but you will have to look carefully to figure this out as many drifts are now
covered up.
Mountain Weather:
We should see a few
more inches of snow this morning before things taper off. Temperatures will be in the teens today with northwest
winds picking up slightly this morning then tapering off as the day progresses. Saturday will bring partly cloudy skies which
will probably coax a large amount of people into the backcountry. It’ll be hard to keep from getting a case of
powder fever but I’d urge people to use caution through this busy weekend.
Announcements:
The Wasatch Powderbird Guides will do recon later today if they get the chance. They will operate outside of the
For an avalanche education class list, click HERE.
If you want to get this avalanche advisory e-mailed to you daily click HERE.
The UAC has temporary job openings for doing avalanche outreach in more rural
areas. Click HERE for info.
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.