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
Wednesday,
February 28, 2007 7:30 am
Good morning, this is Evelyn Lees with
the
Current Conditions:
The February snow machine
is taking a short breather this morning, before clouds increase again this
afternoon and initiate another round of snow.
Temperatures are in the single digits to just below zero this
morning. Winds are very light, generally
5 mph, with gusts to 10. Even the highest
peaks only have gusts to 20 mph. Snow
totals from yesterday’s short, intense storm came in just under a foot at most
locations. Adding up numbers, 30 to 50
inches of snow have fallen in the past week, making trail breaking tough.
Snow and Avalanche Discussion:
Today will be good for
sightseeing. With a window of late
afternoon visibility, reports included: 100% of South
Monitor avalanched naturally, 1/3 to ½ a mile wide, up to 10’ deep. A 900’ wide section of West Monitor went out
to the ground, and a “pocket” 8’ deep and 60’ wide avalanched in No Name. Another natural 2-3’ deep by 100’ wide was observed
in Thomas Fork. In the Ogden area
mountains, there was a
very close call in Hells Canyon, when a person triggered a new snow slide
about a foot deep on a steep, northeast facing slope at about 8,700’. He went for the ride of his life, 1,300’
vertical, was buried up to his eyeballs with a hand sticking out, and walked
away uninjured. The new snow was very
sensitive, reactive to ski cuts and explosives, with some natural activity
observed.
Today the new snow
will still be sensitive on steep slopes, with easily triggered sluffs and soft slabs,
especially where wind drifted. The
drifts will be most widespread on east and northeast facing slopes, but
yesterday’s strong southwesterly winds will have also drifted snow well off the
ridgelines and cross loaded it onto other aspects. Any slide initiating in the
new snow has the potential to break down into deeper weak layers, taking out several
storms worth of snow or even to the ground.
Yesterday’s natural
activity indicates that once again the weak facets near the ground have been
overloaded to the point of failing. A person
can trigger an unsurvivable slide to the ground in a shallow spot. Slides breaking into the old snow can be
triggered remotely from a distance, from below, and are most likely on slopes facing
northwest through northeast through southeast.
Deep avalanches could occur at lower elevations, below 8,500’.
Bottom Line for the
The avalanche warning
has expired. However, a CONSIDERABLE
avalanche danger remains on slopes of about 35 degrees or steeper, especially
those facing northwest through northeast through southeast above about 8,000’. CONSIDERABLE means human triggered slides are probable. Both new
snow slides and deep, unsurvivable slides breaking to the ground can be
triggered by people. People without
excellent route finding and avalanche skills should avoid backcountry travel
today. If you want to hit the steep
slopes, go to a resort. High marking is
not recommended.
Mountain Weather:
A broad upper trough
will keep cold and unstable air over the area today. Skies will be partly clear
this morning, with clouds increasing this afternoon and light snow showers developing. The northerly winds will be light, in the 5
to 10 mph range. Even the most exposed locations
will only have gusts to only 25 mph.
Temperatures will be in the teens at 8,000’ and the single digits at
10,000’. The next disturbance will bring
periods of snow through Friday, with total accumulations of up to 2’ of low
density fluff.
Announcements:
The Wasatch Powderbird Guides didn’t get out yesterday and today will be
in
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.