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

WEDNESDAY, MARCH 20, 2002 07:30 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 Bruce Tremper with the Forest Service Utah Avalanche Center with your backcountry avalanche and mountain weather advisory.  Today is Wednesday, March 20, 2002, and it’s 8:00 a.m.

 

Current Conditions:

Today at noon is the equinox, means that it’s the first day of spring, yahoo, so it’s only fitting that we have spring like weather today, tomorrow and on Friday. There’s still some soft, settled powder on upper elevation north facing slopes but most of the sun exposed slopes have various kinds of sun crusts.

 

Avalanche Conditions:

In late breaking news, backcountry explosive testing this morning by the helicopter company produced several very large avalanches.  The entire upper bowl of Mineral Fork slid this morning as well as the East Fork of Mineral Fork, Red Baldy in White Pine Canyon and an 800 foot wide avalanche between Red and White Baldy.  These are all going at least 4 feet deep, into old snow and are very large dangerous avalanches.  They were easily triggered by explosives, indicating that skiers, boarders and snowmobilers could have easily triggered them as well.  In addition, there were several new avalanches reported from yesterday in the Salt Lake-area mountains.  The most significant one was a natural avalanche in mid Days Fork on a very steep, east facing slope in the rocks which does not see much ski traffic.  It broke 2-5 feet deep and about 300 feet wide.  We’re not sure exactly when this came down but it was probably in the past day.  Also, some skiers kicking cornices along the Patsy Marley ridgeline triggered a wind slab on a steep east facing slope, which stepped deeper into older snow around a rock band that was 2-4 feet deep and about 30 feet wide.  The debris covered up a couple of climbing tracks from other skiers in the area.  Finally, there was some wet activity yesterday.  Backcountry skiers were able to trigger a couple smaller wet slabs on south facing slopes in the Highway to Heaven area.  In addition, there was a natural wet slab off the west face of Timpanogos yesterday that descended about 2000 vertical feet.

 

So today, we have two avalanche problems.  First, there is the lingering deep slab instability.  Very weak faceted snow left over from January and February has been overloaded with all the new snow recently and continues to produce localized, very large avalanches.  There have been a number of very close calls these past few days and two deaths over the weekend.  These seem to be occurring on steep slopes with traditionally thin snowpacks that don’t see much compaction from skiers, boarders and snowmobilers. Although there’s only localized places where you can still trigger them, the consequences of getting caught in one of these monsters would likely be unsurvivable.   Most of them have snapped off trees like toothpicks.  Today, you should continue to avoid slopes steeper than about 35 degrees that have not slid recently.  The hot ticket today would be to play on avalanche paths that have slid recently because they are quite safe and they now have last weekend’s nice powder smoothing out the debris.  Just be careful about not disturbing the un-slid snow.  For a list of what has slid during the past week, call our more detailed report at 364-1591.

 

The second avalanche problem today will be the dramatic warming, which should create quite a few wet sluffs and slabs on steep slopes as they get soggy, especially in the heat of the afternoon.  For instance, this is not a good day to build a jump at the bottom of Superior or Flagstaff gully. 

 

 

 

Bottom Line: 

As usual, it’s hard to put a danger rating on this kind of instability.  Yes, there’s only moderate probability of triggering an avalanche but if you do it will likely be huge and very deadly.  Traditionally thinner snowpack areas on steep slopes which did not slide during the last storm would have a CONSIDERABLE danger.  Also, steep slopes that become soggy with sun and warmer temperatures will rise to a CONSIDERABLE danger today.

 

(Provo Area Mountains)

Same as Salt Lake Mountains.  

 

(Western Uinta Mountains)

The avalanche danger in the Western Uintas is CONSIDERABLE.  Very large and dangerous human triggered avalanches are possible on steep slopes that did not slide recently. 

 

(Ogden Area Mountains)

MODERATE Danger.

 

Mountain Weather:

Today is the first day of spring, so it’s only fitting that we have appropriate weather.  Today should be mostly sunny with possibly some scattered, variable high clouds.  Ridge top winds will blow about 20 mph from the west with ridge top temperatures rising to the lower 30’s.  Down at 8,000’ temperatures will climb into the lower 40’s with an overnight low in the upper teens.  Looks like even warmer on Thursday and possibly Friday, with another storm coming in for the weekend.

 

General Information:

Wasatch Powderbird Guides will be flying two ships today, one in Cardiff, Days and Silver Fork today with a home run in Grizzly Gulch, and a second one in White PIne.  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 [email protected], 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. 

 

Tom Kimbrough will update this advisory by 7:30 on Thursday 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