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, December 01, 2007  7:00 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, December 01, 2007 and it’s about 7:00 am.

 

Current Conditions:

Sneaking in the back door from the south, a small storm has added 3 to 6” of snow in the Logan and Ogden area mountains, 5 to 8” on the Park City side and in the Cottonwoods, with the Provo mountains winners with almost a foot at the 9000’ elevation.  Densities are running in the 8 to 10% range.  Yesterday’s strong, southerly winds decreased in the afternoon once it started to snow, into the 15 to 25 mph range.  This morning, they are still from a southerly direction and less than 15 mph at most stations. Temperatures are in the low to mid 20’s this morning.

 

Turning and riding conditions will be greatly improved, especially in the Cottonwoods and on the Park City side, on shady slopes above about 9,000’ where there was a preexisting snow pack.  Unfortunately, the snow is falling on almost bare ground on most other slopes, including the southeast through westerly facing slopes and at elevations below about 8,500’.  Some trails and roads do have a packed base, which will help with approaches and exits.  The snow pack is shallow, and numerous rocks and stumps lurk just below the surface.  (For Bruce’s field day yesterday, Click here)

 

Avalanche Discussion:

Today’s avalanche danger will be exactly where the best turning and riding conditions are – on steep, upper elevation northerly and easterly facing slopes that had a pre existing snow pack.  I expect most of the activity to be the new snow only, with human triggered loose sluffs and soft slabs possible on steep slopes.  The light fluff that fell Wednesday could act as the weak layer.  Deeper in the snowpack, there are also weak layers of faceted snow.  On a few slopes, it may be possible for people to trigger a slide breaking on this more deeply buried sugary layer.   Because these facets are very variable, I would expect any activity on this layer to be very pockety in nature. (Click here for a snowpit)  But remember, being caught in any size avalanche can be dangerous, especially this time of year where even a small ride can sweep you through terrain features such as rocks.   No avalanches were reported yesterday, and in spite of strong winds, the drifts that formed were generally pockety and not sensitive. 

 

So start thinking avalanche as soon as you leave your vehicle: jump on test slopes, and perform lots of hand pits and pole plants, try to get a feel for the bonding of the new snow and the variability of the old snow.  Be alert for any collapsing or whoomphing, an indication the older faceted snow is failing. 

 

Bottom Line:

Salt Lake, Park City and Ogden area mountains: The avalanche danger is MODERATE on northwest, north and northeast facing slopes steeper than about 35 degrees above about 9,000’ in elevation. Human triggered avalanches are possible.

Provo area mountains: The avalanche danger is CONSIDERABLE above about 10,000’ on steep, shady slopes. The rest of the terrain, including slopes below about 8,500’ and southeast thorough westerly facing slopes, has a generally LOW avalanche danger.  The avalanche danger may increase Sunday if the strong southerly winds in the forecast verify.

 

Mountain Weather: 

Moisture continues to stream northward from Pacific storm system centered to the south of us.  Light to moderate snowfall should continue most of the day, with an additional 5 to 9” possible.  Winds will gradually shift to the northwest and continue to decrease, into the 5 to 10 mph range, with gusts less than 25 mph.  Temperatures will cool into the low teens at 10,000’ by afternoon.  Snowfall will taper off this afternoon as the storm pulls to the east, and skies will become partly cloudy tonight, with only a few lingering snow flurries.  The westerly winds will be light, and temperatures will drop to near 10.  Sunday will bring increasingly strong southwesterly winds, increasing the avalanche danger.

 

Announcements:

 

For an avalanche education class listing, click HERE.  

 

If you want to get this avalanche advisory e-mailed to you daily click HERE.

 

The UAC has job openings.  Click HERE for info.

 

We are in the office most days.  You can reach us by calling 524 5304 or e-mail us at [email protected].  Keep in mind it may take a few days if you are looking for a return message.

 

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 are getting out and see anything we aught to 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.

 

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