Wasatch Cache National Forest

In partnership with: The Friends of the Utah Avalanche Forecast Center, Utah Department of Public Safety Division of Comprehensive Emergency Management, Salt Lake County, and Utah State Parks

 

: http://www.avalanche.org/~uac/

 

Avalanche advisory

Tuesday, NOVEMBER 18, 2003   7:30 am

 

Good morning, this is Andrew McLean with the Forest Service Utah Avalanche Center with your avalanche and mountain weather advisory.  Today is Tuesday, November 18, 2003, and it’s 7:30 a.m. 

 

Current Conditions:

Over the last two days, the Wasatch Mountains remembered what winter was supposed to be like with a furious early season storm.  Yesterday’s main event was 8 – 14” of new snow with 20-30 mph winds and gusts up to 60.  The storm totals are 14 to 26” in the Cottonwood Canyons and up to 24” in the Provo area. This combination of heavier density snow and high winds created an inverted snowpack, with a thick supportable layer on top of the lighter density snow from three days ago.  Today, the winds have settled down and there will be broken clouds and increasing temperatures throughout the day.  Currently it in the mid 20’s at 8,000’ and expected to reach into the high 30’s in the afternoon. 

 

The storm was a mixture of warm, high density snow with some graupel mixed in.  This makes for tough trail breaking, but good turning conditions on the supportable, heavier density snow.  The best bet for good turns is on sheltered, lower angle slopes that haven’t been hammered by the wind.

 

Avalanche Conditions:

These high winds drifted snow onto East through Northeast facing slopes, creating dangerous wind slabs and sensitive cornices.  Yesterday people found thick wind slabs that are sensitive to human triggers on the lee side of ridges, which may crack, but not go anywhere if the angle is 35 degrees or less, but will run full track on steeper slopes.  Explosive testing at the resorts produced numerous results yesterday with some slopes releasing multiple times.  The high winds have loaded slopes well off the ridgeline, causing avalanches to trigger lower down on the slopes than might be expected.  At higher elevation, stick to ridge lines and avoid obvious wind loaded pillows.

                                                                                                                                                                                          

Bottom Line (Salt Lake, Park City and Ogden area mountains):

Danger is CONSIDERABLE on any steep slope with recent wind deposits above 9,000 with slope angles steeper than 35 degrees.  You’ll find them mostly on east and northeast facing slopes.  It is MODERATE on all aspects below 9,000’.

 

Provo area mountains:  The avalanche danger is CONSIDERABLE above 9000’ on slopes steeper than 35 degrees and MODERATE on all aspects below 9,000’ with slope angles less than about 32 degrees.

 

Mountain Weather:

Expect scattered clouds with warming and clearing throughout today and some light snow showers.  The winds will shift to the west and the snow will taper off this evening as a high pressure system moves overhead.  The big news is that on Wednesday, a mild southwest flow will be developing along with dramatically warmer temperatures in the upper 40’s and possibly 50’s in the mountains, in front of an approaching cold front on Thursday.  This is anticipated to bring a potentially major storm on Friday, with snow expected in the Salt Lake Valley over the weekend.

 

For specific digital forecasts for selected mountain areas from the National Weather Service, click the links below or choose your own specific location at the National Weather Service Digital Forecast Page:

 

3-Day Table

3-Day Graph

7-Day Table

Ogden Mountains

Ogden Mountains

Ogden Mountains

SLC Mountains

SLC Mountains

SLC Mountains

Provo Mountains

Provo Mountains

Provo Mountains

 

 

General Information:

The Alta Ski Area will be closed to uphill traffic because of avalanche control and slope preparation for their opening on Thursday.

 

If you are getting into the backcountry, please give us a call and let us know what you’re seeing, especially if you trigger an avalanche.  You can leave a message at 524-5304 or 1-800-662-4140.  Or you can e-mail an observation to [email protected] .org, or you can fax an observation to 801-524-4030.

 

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. 

 

Evelyn Lees will be updating this advisory tomorrow morning.

Thanks for calling.

_____________________________________________________________________________

For more detailed weather information go to our Mountain Weather Advisory

National Weather Service - Salt Lake City - Snow.

For an explanation of avalanche danger ratings:

http://www.avalanche.org/usdanger.htm