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

THURsday, MARCH 7, 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 Thursday, March 7, 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:

Snowfall began in the mountains about 4:00 a.m., with probably a few inches of accumulation by now. Winds are westerly 10 to 25 mph over the high ridges, with gusts to 35. 8,000 foot temperatures are in the mid twenties.

Avalanche Conditions:

Over the past week there have been a surprising number of triggered avalanches in the backcountry, several in the Wasatch and others in the Uintas. Yesterday, I was caught and carried in a loose snow sluff; a ride that was a little spookier than I enjoy. Now northern Utah is about to get a hopefully decent storm, really the first since late January. During this rather dry winter our snowpack has developed numerous weak layers and crusts that are bound to cause plenty of avalanches as new snow builds up. Another clue to possible events over the next several days is that despite the lack of storms in February, the avalanche activity has continued to persist, accentuated each time the winds picked up or we got a couple of inches of snow. If the mountains get a really big dump, lots of slopes will avalanche, cleaning out some of the weak layers and we can start over. For today, at least, with only a few inches of new snow, that doesn’t appear to be the case. But the avalanche danger is rising today and may take a big jump tonight.

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. I think the recent warm temperatures have strengthened the lower elevation snowpack. Slides in the new snow may step down into deeper layers, especially on northwest, north and east facing slopes. As this storm develops today and Friday and 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.

Weak underlying snow is most widespread in the Provo and Uinta mountains.

Bottom Line:

The danger of human triggered avalanches is MODERATE this morning on mid and upper elevation wind drifted slopes, steeper than about 35 degrees. Human triggered avalanches are possible. The danger may rise to CONSIDERABLE as snowfall and wind continue today. Shallow new snow avalanches may step down into deeper layers, creating more dangerous slides.

(Provo Area Mountains and Western Uinta Mountains)

These areas have had a thin snowpack most of the winter, and the 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:

Skies will be overcast today with snow, heavy at time this morning, becoming more showery during the afternoon. Winds will be westerly 15 to 25 mph this morning, then shifting back to the south and southwest and increasing during the afternoon. High temperatures will be near 30 degrees at 8,000 feet and in the twenties at 10,000. At strong cold front will arrive about midnight tonight, with strong winds, possibly some lightning and heavy snow. Storm totals by sometime Friday could be about 10 to 18 inches.

General Information:

The Wasatch Powderbird Guides will probably not be flying today, but if they do get out, will be in the Silver, Day’s, Cardiff, and Mineral Fork drainages of Big Cottonwood Canyon and in the Porter Fork and Alexander Basin drainages of Mill Creek. 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.

I will update this advisory by 7:30 on Friday 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