Wasatch Cache National Forest
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 Salt Lake County.

“keeping you on top”

AVALANCHE ADVISORY

Saturday, March 15, 2008  7:30 am
Good morning, this is Evelyn Lees with the Forest Service Utah Avalanche Center with your backcountry avalanche and mountain weather advisory.  Today is Saturday, March 15, 2008 and it’s about 7:30 am. 

 

Current Conditions:

Under partly cloudy skies, temperatures are in single digits to midteens this morning.  The west to southwesterly winds are in the 10 to 15 mph range, with gusts to 25.  Speeds across the highest peaks are averaging 20 mph, with gusts to 35.  Storm totals are about 7” or less in the Ogden and Provo mountains, 8 to 14” on the Park City side, and 15 to 25 inches in the Cottonwoods.  You can still feel the old snow surface on slopes with less than about a foot of new snow, slopes with more snow…it’s classic Utah POWDER.

 

Snow and Avalanche Discussion:

Yesterday was a very active day, with widespread sluffing of the new snow  on steep slopes of all aspects, both natural and easily triggered.  Many of these were large enough to catch and carry a person, some running hundreds of feet.  Southeast facing slopes were particularly active, with easily triggered slides 30 to 60’ wide running on the crusts, both above Alta and in Dutch Draw, where a person was caught and took a 100’ ride. 

 

Then there were a few larger more serious avalanches triggered.  In Georges Bowl, Cardiff Fork, one skier took a 100’ ride at 9,000', and another slide was triggered remotely from along the ridgeline, 150 feet wide by 18" deep, running about 1000’ and pulling out another small pocket.  Along the Twin Lakes pass-Patsy Marley ridgeline at 10,000', a very small soft cornice drop triggered a slide 300’ wide and 1-2 feet deep.  These slides were all on east northeast facing slopes, failing on near surface facets that formed during the past few weeks.  Details are on the early morning line, option 8, and will be updated later on the web. 

 

Today will be tricky.  On many steep slopes, the only activity will be human triggered new snow sluffs and shallow soft slabs, easily managed with ski cuts and cornice drops.  However, here and there, people could be surprised with a deeper slide failing on the weak, sugary old snow surface.  These slides will be up to 2 feet deep, a couple of hundred feet wide, and could break out above you or be triggered from a distance.  They will take you for a ride, potentially long, and could bury you.  This weak layer is spotty, which makes the problem even trickier for the backcountry user. There will be a rising danger this afternoon if the forecast of periods of heavy snowfall verify, especially with any increase in wind. 

 

This morning, any periods of direct sun or thin clouds will make the snow on steep southeast and south facing sunny slopes more sensitive, with damp sluffs or slabs possible.  Mid and low elevation shady slopes may get in on the damp snow action, too, if thin high clouds are over the area for a while.   

 

Bottom Line for the Salt Lake and Park City mountains:

All steep mid and upper elevation slopes have at least a MODERATE danger today, with human triggered sluffs and soft slabs possible, some far running and with enough punch to catch and carry a person.  There are pockets of CONSIDERABLE avalanche danger on steep northwest through easterly facing slopes this morning, where in isolated places avalanches up to 2 feet deep can be triggered, both on the slope and from a distance.  This danger will become more widespread this afternoon, with additional snowfall and wind in the forecast.

 

Ogden, and Provo mountains: The avalanche danger is MODERATE on all steep slopes, especially those facing northwest through east.  Easily triggered soft slabs and sluffs are possible.  The avalanche danger may increase this afternoon with additional snow and wind.

 

Practice safe travel procedures today, of only one person on a steep slope at a time both ascending and descending, and get out of the way at the bottom.  With lots of people in the backcountry, if you are kicking cornices or ski cutting – make sure there is no one below you – any slide triggered may run further than expected, or could triggering a second slide to the side. 

 

Mountain Weather:

Another Pacific storm system is approaching, with the cold front forecast to reach the northern mountains mid afternoon.  Increasing clouds this morning, with scattered snow showers developing.  Once the cold front arrives this afternoon, periods of heavy snowfall are possible, with 3 to 5” expected this afternoon, and another 6 to 10” possible tonight.  Temperatures today will be near freezing at 8,000’ and in the mid teens at 10,000’.  The southwesterly winds will be in the 10 to 20 mph range, with gusts to 30, and gusts to 40 across the most exposed terrain.  More snow is possible on Sunday, accompanied by moderate to strong northwesterly winds.

 

Announcements
The Black Diamond Wasatch POWDERkeg race, being run this morning in Grizzly Gulch near Alta, so the area will be congested until about noon.

 

The Wasatch Powderbird Guides did not fly Friday due to weather, but will try to get out for a while this morning.  They will have one ship in Cardiff, Days, Silver, Grizzly and White Pine, with a second ship in American Fork and Cascade.  For more detailed information please call (801) 742-2800 or go to their daily blog.

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).

Watch video tututorials and fieldwork from UAC staff at our YouTube channel.

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.

Drew Hardesty will update this advisory by 7:30 on Sunday morning.