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

SuNDAY, NOVEMBER 16, 2003   7:30 am

 

Good morning, this is Drew Hardesty with the Forest Service Utah Avalanche Center with your avalanche and mountain weather advisory.  Today is Sunday, November 16, 2003, and it’s 7:30 a.m. 

 

Current Conditions:

It started snowing just before midnight and as of 6am the mountains have picked up another 3-4”, with an additional 3-6” possible over the course of the day.  Across the range, settled snow depths are 2-4 feet and the coverage is generally pretty good.  Mountain temperatures this morning are in the 20’s and winds remain light out of the south and southwest.  Turning and riding conditions are excellent on the mid and upper elevation northerly aspects, with newly buried crusts on the sunny side of the compass. 

 

Avalanche Conditions:

Yesterday was the first day in exactly a week that no new natural or human triggered avalanches were reported from the backcountry.  Since last Sunday, there have been numerous backcountry slides, including some close calls where skiers have been caught or have had to ski out of avalanches they have unintentionally triggered.  All these avalanches fractured on the weak layer of frost or “surface hoar” that formed on the surface of the snow on November 7th and 8th.   Most of the problem seems to be above about 9,000 feet on northerly through easterly facing slopes but it’s quite pockety: you can find it in the upper elevations of one drainage, but not the drainage next to it.  With quiet conditions yesterday, my feeling is that time and the warm temperatures have helped the buried surface hoar adjust to its load, effectively releasing the tension of the rubber band.  But it’s not so simple:  another layer of surface hoar formed Friday night and is now buried under last night’s snowfall.  If we see another 4-6” today, the avalanche problems may include new snow avalanches on the most recent weak surface snow and then the potential of the new load reactivating the deeper buried surface hoar.  Regardless, play it conservative and stick to slopes under about 32 degrees.   If you must push slope angles today, do lot’s of digging in the snow and do stress tests to look for the characteristic clean, spring-loaded shears on a thin layer of sparkly feather-like crystals.

 

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

The avalanche danger is MODERATE, or localized today on slopes facing the northwest through east quadrants of the compass, above about 9,000’, and steeper than about 34 degrees.  Moderate implies that human triggered avalanches are possible.  If we see snow totals of about a foot, the danger will rise accordingly: both layers of surface hoar may become reactive where both natural and human triggered avalanches will become more likely. 

 

Mountain Weather:

A weak storm currently moving through should drop an additional 3-6” today with light southwest and westerly winds along the ridgetops.  8000’ temps will be in the high 20’s with 10,000’ temps near 20 degrees.  Tonight a fast moving storm moving down from the Pacific northwest should give us another good burst of snow after midnight and into tomorrow.  High pressure fills in for midweek, with another, stronger system for early 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:

Starting on Monday, 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 801-524-6301.

 

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. 

 

I will update 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