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,
January 11, 2008 7:30 am
Good morning, this is Brett Kobernik with
the
Bruce will be giving a
talk called "The
Science of Avalanches" in
Current Conditions:
Yesterdays snow
surface ranged from excellent settled powder to deteriorating conditions due to
wind at the upper elevations and warmer temperatures down low. Overnight temperatures at the higher
elevations were in the upper teens and in the mid 20s at the mid and lower
elevations and currently dropping. Winds
are westerly and have been gradually increasing in speed over the last few
hours. Speeds are similar to yesterday
morning in the 10 to 20 mph range at the mid ridgelines and gusting into the
50s at some of the more exposed peaks. A
light mist was noted late Thursday afternoon at lower elevations with rime occurring
at higher locations. This was noted in
Big Cottonwood, the
Avalanche Discussion:
People who
were out on Thursday reported stabilizing snow for the most part. You could still produce fairly clean shears
within the newer snow and there was still some minor cracking but no shooting
cracks reported. The winds were
producing some large sensitive soft cornices that released easily with a
kick. They did not produce any
significant avalanches as they hit slopes below. The mist and or rime event probably produced
a thin crust which will be covered with snow today. This may or may not present problems. However it appears that this event was fairly
widespread and we do know that rime crusts can present problems especially
after they are buried and with associated faceting. This is something that you snow nerds should
monitor.
The recent
series of storms has pushed us into normal or above snowpack depths and water content
for this time of the season. A number of
stations are near as much snow as all of last year. Charts for: BEN
LOMOND, FARMINGTON,
MILL
D NORTH, THAYNES,
SNOWBIRD.
There are
a few recent PHOTOS
and SNOWPITS
of interest.
For today
wind drifted snow will be the main focus.
Any time snow gets transported by the wind it can quickly form large
sensitive drifts and or slabs. Sometimes
these can be quite sensitive and sometimes they stay in place. Indicators include cornice formation, “pillowy”
looking drifts, a stiff feel to the snow surface, and cracking within the snow
while traveling on it. Small wind
drifted test slopes should be used to get a handle on how sensitive the drifts
are. Slope cuts are an affective tool as
well. Always approach cornices with
caution as they may break off farther back then expected.
While many
areas with a deep snowpack seem to have stabilized, I’ll continue to remind
people about the possibility for a deep slab release. You probably need a combination of quite a
steep slope, a large trigger, and thinner snowpack areas are more suspect. Use a ski pole or an avalanche probe to poke
through the snowpack to check the depth and feel for loose snow near the
ground. Don’t let other ski, snowboard,
or snowmobile tracks on visable slopes dictate your
stability evaluation. Do your
homework. You might surprisingly find
something you don’t like.
Bottom Line for the
The
avalanche danger starts out at MODERATE this
morning. The avalanche danger is rising
today due to winds and new snow. It may
reach CONSIDERABLE at the upper
elevations which are most exposed to the winds.
North easterly and south easterly facing upper elevation slopes should
be evaluated very carefully.
Mountain Weather:
Westerly winds will blow
through the morning at their current speeds or a bit stronger before tapering
off later this afternoon. The first
punch of this storm moved through this morning producing a few inches of snow
in many areas. We’ll see a lull then a
good chance for snow between about 10am and 4pm this afternoon. 4 to 8 inches are possible with a quarter to
a half inch of water weight. A ridge of
high pressure builds in but we’ll be on the down slope side of it with a little
moisture spilling over to produce a few chances for snow flurries over the
weekend.
Announcements
The Wasatch Powderbird Guides yesterday American Fork,
The avalanche beacon parks are up and running at Solitude, Snowbird and
Canyons.
Great places to practice by yourself or with
friends.
The UAC depends on contributions from users like you to support our
work. To find out more about how you can support our efforts to continue
providing the avalanche forecasting and education that you expect please
visit our Friends page.
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.