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
Saturday,
March 10, 2007 7:30 am
Good morning, this is Evelyn Lees with
the
Current Conditions:
A weak storm system
moving through northern Utah this morning has produced an additional 1 to 3” of
dense snow, with the rain/snow line around 7,000’. This is on top of the 4 to 7” of dense snow
from Thursday. After a warm night,
cooler air is moving in with the front, and
temperatures at all but the lowest elevations have dropped below freezing, with
10,000’ temperatures down into the mid 20’s.
Winds are in the process of shifting from southwest to northwest, and
are generally in the 5 to 15 mph range, with gusts to 30. The best place to look for cold dry powder is
on northerly facing slopes, above about 9,000’.
Snow and Avalanche Discussion:
The new snow continued
to be sensitive yesterday, especially on north and east facing slopes and in
wind drifted areas. Dry
soft slabs, wet slabs, and wet
sluffs were easily triggered. All of
these were small, up to 6" deep x 50' wide, involved only new snow, but
were moderately long running.
Today, there will be
the same three avalanche problems Bruce listed yesterday. First, you may be able to trigger relatively
shallow, soft slabs within the new snow from the past two storms, especially on
steep slopes with recent wind drifts. Second, you’ll be able to trigger wet
loose sluffs and a few wet slabs on steep slopes of almost all aspects and
elevations as the snow heats up with sun and daytime heating,
and at the lower elevations where it rained last night. Old bed surfaces with new snow will also be
sensitive. All these new snow slides
pack just enough punch to knock you off your feet and carry you, so don’t get
surprised and shoved off a cliff or into a terrain trap such as a gully.
And finally, there are
still isolated places on northerly and easterly facing slopes where you could
trigger a hard-slab avalanche 2-5 feet deep.
This would be most likely in a thinner snowpack area or in a shallow
rocky place, and with a large trigger such as two or more people or snowmobiles
on the slope at the same time.
Bottom Line for the
The avalanche danger
is MODERATE on slopes of about 35 degrees and
steeper, especially with recent drifts of wind blown snow or where the snow is
heating up from the warm temperatures and sun.
There is also a MODERATE danger of
triggering a large, hard-slab avalanche on slopes that face the north and east
quadrants of the compass, especially in thinner snowpack areas.
Mountain Weather:
A weak storm system is
moving south through the area, with high pressure rapidly building in this
afternoon. Expect a few more snow
showers through mid morning, with skies becoming partly sunny by
afternoon. Temperatures will warm to
near 40 at 8,000’ and be in the low 20’s at 10,000’. The winds are in the process of shifting to
the northwest, and will average 5 to 15 mph at most locations, with the highest
peaks having gusts in the 40’s and 50’s this morning. High pressure will dominate through mid week,
with temperatures rapidly warming into the mid to upper 30’s at 10,000’ on
Sunday.
Announcements:
Yesterday, the Wasatch Powderbird Guides was in
The UAC and ACE are offering a day long Women’s Avalanche
Awareness class at Alta on March 22nd covering beacon use and basic safe
travel, terrain and snowpack information, for a nominal fee. For more details go to: www.altaarts.org.
Listen to the
advisory. Try our new streaming audio or
podcasts
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 a list of avalanche
classes, click HERE
For our classic text advisory click HERE.
To sign up for automated e-mails of our graphical advisory click HERE
We appreciate all the great
snowpack and avalanche observations we’ve been getting, so keep leaving us
messages 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.
Drew Hardesty will update this advisory by 7:30 on Sunday morning, and
thanks for calling.