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

 

                                       The FS Utah Avalanche Center’s Home page has moved!                

Our new URL is: http://www.avalanche.org/~uac/ please update your Bookmarks!

 

Avalanche advisory

FRIDay,  MARCH 8, 2002  7:30 AM

 

NEW!

If you want this forecast e-mailed to you each day, click here.

If you want to see photos of recent avalanches, click here.

If you want to see photos of avalanche terrain, click here.

If you want recent archives of this advisory, click here.

 

Good morning, this is Tom Kimbrough with the Forest Service Utah Avalanche Center with your backcountry avalanche and mountain weather advisory.  Today is Friday, March 8, 2002, and it’s 7:30 a.m.

 

Don’t miss the Banff Mountain Film Festival at the U of U’s Kingsbury Hall on March 12 and 13, at 7pm.  Tickets are available at the Kingsbury Hall ticket office, Art-Tix, the University of Utah’s Outdoor Program (581-8516), and REI (486-2100).  Don’t miss this great benefit for the Friends of the Utah Avalanche Center!

 

Current Conditions:

The expected cold front arrived in the Salt Lake area a little after midnight with heavy snow and strong westerly winds.  Snow was coming down at several inches an hour for awhile as the winds hit 30 to 60 mph on the high peaks.  Reports also indicate that the winds got down into all elevations.  Storm totals since yesterday morning are around a foot or better in most places, with 14 to 18 inches in the Cottonwood Canyons.  Yesterday’s snow was quite elevation dependant so I expect some ridge lines, especially around the rim of the Cottonwoods, have a good 2 feet of fresh snow.  So far, the Provo mountains don’t seem to have gotten much out of last night’s cold front, however I wouldn’t be surprised if some of those upper elevations don’t also have about a foot.  Mountain temperatures dropped sharply with the cold front and are now in the teens. 

 

Avalanche Conditions:

There is an avalanche warning in effect for the northern Utah Mountains.  Very rapid overnight loading of an exceptionally weak snowpack mean that both human triggered and natural avalanches are likely in many areas today.  Travel in avalanche terrain is not recommended. 

 

During this rather dry winter our snowpack has developed numerous weak layers and crusts that will exacerbate the effects of the current storm. The weak layers are weakest and most widespread at mid and upper elevations on northerly facing slopes that don’t get much sun.  Southerly facing slopes are crusted under the new snow and the crust will provide a good sliding surface.  East and west facing slopes are in between with a variety of crusts and weak layers.  Wind crusts, slabs and old bed surfaces also complicate the picture.  At least the recent warm temperatures strengthened the lower elevation snowpack.  Although yesterday’s new snow bonded fairly well to the older crusts, layers of graupel in yesterday’s snow will be a likely weak layer today.  But of more concern is that slides in the new snow may step down into deeper layers, especially on northwest, north and east facing slopes.  If you head into the backcountry today or over the weekend, be conservative and defensive in your backcountry travel.  Watch for collapsing and cracking in the new snow.  Keep to lower angle slopes.  With these types of weak layers, slopes may be remotely triggered so watch the angle of slopes above and to your side.  Carry beacons and avalanche rescue gear and keep your party spread out.

 

This morning we don’t yet have a good handle on which of the more remote areas received significant new snow accumulations but some of the weakest underlying snow is most widespread in the Provo and Uinta mountains.  All of Utah’s mountains have an unusually weak snowpack this year.  Where ever there is more than about 6 or 8 inches of new snow and in all wind exposed areas, the avalanche danger is likely to be high today.  

 

Depending on how much clearing there is this afternoon, some sunny slopes could have a few wet slides as they heat up later today.

 

Bottom Line: 

The danger of human triggered avalanches is HIGH today on all slopes steeper than about 30 degrees, especially where wind drifted.  Human triggered and natural avalanches are likely.  Avoid steep backcountry slopes and avalanche run-out areas.  Avalanches in the new snow may break into deeper layers, creating large and very dangerous slides.

 

(Provo Area Mountains and Western Uinta Mountains)

These areas have had a thin snowpack most of the winter and sugary weak snow is more common than in the Cottonwood Canyons.  The danger of human triggered avalanches is more widespread in the Provo and Western Uinta Mountains, especially where wind drifted. 

 

(Ogden Area Mountains)

Same as above.

 

Mountain Weather:

This cold front is moving fast and will exit northern Utah later today.  Snowfall will taper off in many areas this morning but some places like the Cottonwood Canyons will probably continue to get snow for most of the morning.  Skies will begin to clear later this afternoon.  Winds will also decrease this morning and shift more northerly.  High temperatures will stay in the teens today.  High pressure will move into Utah on Saturday, promising fine weather but with plenty of continuing avalanche potential.

 

General Information:

The Wasatch Powderbird Guides will not be flying today.  For more information call 521-6040 ext. 5280.

 

To report backcountry snow and avalanche conditions, especially if you observe or trigger an avalanche, you can leave a message at (801) 524-5304 or 1-800-662-4140.  Or you can e-mail an observation to uacobs@avalanche .org, or you can fax an observation to 801-524-6301.

 

For more detailed mountain weather and avalanche information, your can call 801-364-1591, which we’ll try to have updated by around noon each day.

 

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 update this advisory by 7:30 on Saturday 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