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

Wednesday, January 09, 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 Wednesday, January 09, 2008 and it’s about 7:30 am.

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.

Current Conditions:

As another storm hits the mountains, powder is starting to seem like a renewable resource. Storm totals as of 6 am are up to 17 inches in the Ogden mountains, about a foot in the Cottonwoods, and 6 to 8” in Park City and Provo mountains. Densities are running a fluffy 5% to 7%. Yesterday, track erasing southwesterly winds picked up in the afternoon, with many ridgelines and open bowls having sustained periods of 20 to 30 mph averages, with gusts in the 50’s, which continued into the night. This morning, winds are in the process of shifting to the northwest and have decreased into the 10 to 20 mph range at all but a few locations. Temperatures are in the teens to low 20’s.

Avalanche Discussion:

No new avalanches were reported from the backcountry yesterday, though one deep hard slab was triggered with explosives at a Cottonwood resort on an upper elevation, northwesterly facing slope.

The most widespread avalanche concern today will be new snow sluffs and soft slabs, especially in wind effected terrain. This new snow sensitivity will increase any time there is a spike in precipitation rates where you are, or the winds increase. While today’s new wind drifts will be easy to spot, last night's drifts are now hidden. Yesterday’s strong southwesterly winds loaded both along the ridgelines and at mid and lower elevations around terrain features and breakovers. Strong northwesterly wind gusts are possible this afternoon. While the heaviest wind loading will be on slopes facing the east half of the compass, drifts will be cross loaded on to other aspects. Cornices could be sensitive, breaking more easily and further back than expected.

The chronic problem of weak faceted snow near the ground has not gone away. One to two inches of water weight is being rapidly loaded onto the snowpack, increasing the possibility of triggering one of these deep slides either from a thin snowpack area or with a new snow slide. The wide variation of the snowpack within the forecast area makes it difficult to forecast exactly where these deep slides will occur.

Bottom Line for the Ogden, Salt Lake, Park City and Provo area mountains:

The avalanche danger is CONSIDERABLE on and below slopes of about 35 degrees and steeper, especially with recent drifts of wind blown snow, which may be hidden beneath the most recent snow. CONSIDERABLE means human triggered avalanches are likely and natural avalanches possible. Cornices will be sensitive and could break back further than expected. There also continue to be isolated places where a person could trigger a deep, dangerous slide, breaking out near the ground. Slopes less steep than about 35 degrees that are not in runout zones have a generally LOW avalanche danger.

Mountain Weather:

Heavy snowfall should continue into late morning, before becoming more showery this afternoon, with an additional 6 to 9” possible today. Winds are shifting to the northwest, and will generally be in the 15 to 25 mph range. There is the potential for strong, 50 to 70 mph gusts this afternoon in the higher terrain. Temperatures will be near 20 at 8,000’ and drop into the single digits at 10,000’. Several weaker disturbances will bring periods of light snow Thursday through Saturday.

Announcements
The Wasatch Powderbird Guides did not fly yesterday and will not fly today due to weather. For more information, call them at 801-742-2800.

Solitude’s beacon park is now up and running, and ready for use. It’s FREE and located just off the northwest corner of the lower lot.

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.

Bruce Tremper will update this advisory by 7:30 on Thursday morning.