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
Thursday,
January 24, 2008 7:30 am
Good morning, this is Bruce Tremper with
the
Current Conditions:
Yesterday up above the
valley fog, we had bluebird, clear skies with about a foot of very nice
powder. The slopes that face the south
half of the compass are sun crusted.
This morning, we have valley fog once again with ridgetop-level
clouds. Temperatures are around 15
degrees and the southwest ridge top winds have picked up to 15 mph and 20 mph
on the highest peaks from the south. A
weak system later today and Friday will give us light snow showers this
afternoon through Friday, which probably won’t add up to more than about 5
inches.
Avalanche Discussion:
Yesterday there was no
significant avalanche activity despite people aggressively tracking up most
slopes. Skiers triggered some minor soft
slabs high in Cardiac Bowl along the ridge but otherwise everything stayed in
place quite well.
Looking at the weather
forecast, the mountains will almost certainly roar with significant avalanche
activity over the next week starting on Sunday.
When a big storm approaches, avalanche geeks like us carefully map out the
present snow surface conditions because the layers on the surface today will
become the weak layer responsible for avalanches when we slap a slab of new
snow on top of them. Potential weak
layers are much easier to see before they get buried than afterwards. The clear skies and cold temperatures over
the past couple days created widespread areas of weak, near-surface faceted
snow and surface hoar on the snow surface and it will not take too much to
overload this very weak snow. The
southerly facing slopes got cooked down these past couple days, so they may not
have as much weak, surface snow, they do have a slick sun crust, which may also
produce future avalanches, but probably will not last as long.
I suspect that the weak storm later today and Friday will not add enough weight
to overload these layers but the Sunday-Monday storm definitely will. Today with the winds increasing to 20 mph
from the south along the ridges, you will need to watch for the usual wind slab
development mostly along the upper elevation ridges. Out of the wind loaded areas, if we get more
than 5 inches of snow or if the snow is denser than we expect, then you will
need to watch for soft slabs on the aforementioned, weak snow surface.
Finally, if you plan to get out this weekend, remember that we expect a high
avalanche danger for Sunday and Monday from a very powerful storm with high
winds and heavy snow.
Bottom Line for the
The
avalanche danger is mostly LOW
this morning and will rise to MODERATE on steep
slopes with recent deposits of wind drifted snow this afternoon and on Friday. For the extended outlook, expect HIGH avalanche danger on Sunday and Monday.
Mountain Weather:
We will have a weak
disturbance later today and on Friday, which will bring about 5 inches of new
snow with 20 mph ridge top winds from the south and southwest. Today, expect increasing and lowering clouds
with ridge top temperatures near the mid teens and 8,000’ temperatures around
25 degrees.
Extended forecast:
The big news is a potentially very powerful storm for Sunday and Monday. Saturday should be the warm and calm before
the storm with near freezing temperatures and sunny skies. Sunday, we will have a powerful blast of
tropical moisture from the southwest with ridge top winds of 60 mph with much
higher gusts, followed by a strong cold front from the northwest on Monday. Then, the rest of the week looks very snowy
as well with several more snow storms from the west and northwest.
Announcements
Yesterday, Wasatch Powderbird Guides flew
in Mineral,
Tonight, there will be a cool, panel discussion on risk and decision making in
outdoor activities, which will include Ian McCammon, an expert on human factors
in avalanche accidents as well as myself and several others. It will be at the Salt
The second annual avalanche awareness
snowmobile ride is Saturday, February 2nd and proceeds will help
support snowmobile specific avalanche awareness projects. Details can be found at http://www.avarides.com/
Backcountry Awareness Week is February 8-10th,
featuring a Friday night fundraising dinner with guest speaker David Oliver Relin, author of the New York Times bestseller Three
Cups of Tea: One Man's
If you want to get this avalanche advisory e-mailed to you daily click HERE.
UDOT highway avalanche control work info can be
found by calling (801) 975-4838.
Our statewide tollfree line is 1-888-999-4019 (early morning, option 8).
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.
If you see any avalanches or interesting snow conditions, please leave us 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.
Brett Kobernik will update this advisory by 7:30 on Friday morning.