Uintas Avalanche Advisory

Forecaster: Craig Gordon

SPECIAL ANNOUNCEMENT

Many thanks to all who attended yesterday’s Avy Ride… what an insanely deep day of powder riding! Big thanks to the athletes from Boondockers and Thunderstruck for taking time out of their very busy schedules to help support a great cause and to the Utah Snowmobile Association and in particular, Curt Kennedy for their very generous monetary contributions to the Avalanche Center. All who attended are helping us save lives, keeping riders on top of the greatest snow on earth, rather than buried beneath it.


BOTTOM LINE

Danger by aspect and elevation on slopes approaching 35° or steeper.
(click HERE for tomorrow's danger rating)


Danger Rose Tutorial

At mid and upper elevations especially at and above treeline, the avalanche danger is a Level 4 (HIGH) and dangerous avalanche conditions exist. Human triggered avalanches are likely, particularly on steep wind drifted slopes in terrain facing the north half of the compass.

In addition, a widespread and persistent layer of surface hoar exists throughout the range and human triggered avalanches can break into this deeply buried weak layer, creating a large and dangerous avalanche. Those without expert snow assessment skills should avoid upper elevation slopes facing Northwest, North, Northeast, and East where a Level 4 (HIGH) avalanche danger exists.

Out of the wind an entirely different avalanche dragon will be found, particularly on mid elevation slopes facing the south half of the compass where you’ll be dealing with storm snow instabilities and perhaps a recent wind drift or two. A Level 2 (MODERATE) avalanche danger exists on these slopes and human triggered avalanches are possible.

A Level 1 (LOW) danger exists on low angle, low elevation terrain, especially those with no steep slopes above or adjacent to where you’re riding.


CURRENT CONDITIONS

Skies are starting to clear in the wake of the multi-day storm and temperatures are in the mid teens and low 20’s. Southerly winds remained strong along the ridges yesterday, but died off around midnight and are currently blowing 10-20 mph with a few gusts in the 30’s along the highest ridges. The latest storm delivered 2’-3’ of new snow across the range and the riding and turning conditions are the deepest they’ve been all year.


RECENT ACTIVITY

A few pockety soft slabs, running within the new storm snow were triggered yesterday along the ridges, but even more spooky where the booming collapses and loud audible whoomphs.

Very large and dangerous natural avalanches were reported during the week with the biggest occurring in Super Bowl. The tree snapping slide was several hundred yards wide and broke deep into the buried surface hoar layer. Additional avalanches occurred along the ridge and Ted got a peak at these yesterday before the weather window slammed shut.

In addition, a very close call last Thursday involved six sledders and a human triggered avalanche near Humpy Peak. No injuries were reported although a few sleds had to be towed out after being damaged by the slide. As the weekend progressed we went through a natural avalanche cycle that saw crowns up to 3' in depth.

Big thanks to all those who submitted observations. The information is GREATLY appreciated!


THREAT #1

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

Wind drifts along the upper elevation ridgelines remained sensitive to the weight of a rider yesterday and new storm snow avalanches were easy to trigger, even from a distance. The good news is the hair trigger instabilities have settled somewhat in the past 24 hours. The bad news is, as the snow gains strength the avalanches you trigger become deeper, wider, and more dangerous. The best bet is to exercise some patience and continue avoiding steep, wind drifted slopes, especially at mid and upper elevations. That doesn’t mean you have to stay at home and hide under the bed. The beauty of riding a sled is, with all the great bottomless snow out there, you don’t even have to mess around with avalanche terrain to have fun. You can find a low angle meadow and carve it up all day long and have a blast.


THREAT #2

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

Nothing has changed with our buried and preserved layer of surface hoar. As a matter of fact, we continue to find this distinct layer alive and reactive in our snowpit tests and much of the recent natural avalanche cycle failed on this notoriously tricky weak layer. While deep, dangerous avalanches are becoming more difficult to trigger, I’m not convinced we’re out of the woods just yet, and the consequences of triggering a slide that breaks deep into the surface hoar layer will result in a catastrophically dangerous slide. Very tricky avalanche conditions exist, so if you are getting out on the snow, stick to low angle slopes or meadows, especially those with no steep slopes above or connected to where you’re riding.


MOUNTAIN WEATHER

Partly cloudy skies, generally light winds, and warming temperatures are on tap as a zonal flow develops over the region through about mid week. Winds will begin shifting to the west and northwest later today, but remain manageable, in the 10-20 mph range. Temperatures climb into the mid and upper 20’s, before diving into the single digits overnight, under clearing skies. Quiet weather remains in place through about Wednesday and then it looks like a return to an active pattern for the second half of the week.


GENERAL ANNOUNCEMENTS

The information in this advisory expires 24 hours after the date and time posted, but will be updated by 7:00 AM Wednesday, Mar. 2nd, 2011.

If you’re getting out and about and trigger an avalanche or see anything interesting please let us know here. Or drop Craig an email : craig@utahavalanchecenter.org or call 801-231-2170

The western Uinta advisory program is going full tilt and forecasts will be issued by 7:00 AM on Wednesday, Saturday, Sunday and all holidays.


This information does not apply to developed ski areas or highways where avalanche control is normally done.  This advisory is from the U.S.D.A. Forest Service, which is solely responsible for its content. This advisory describes general avalanche conditions and local variations always occur.


This advisory provided by the USDA Forest Service, in partnership with:

The Friends of the Utah Avalanche Center, Utah Division of State Parks and Recreation, Utah Division of Emergency Management, Salt Lake County, Salt Lake Unified Fire Authority and the friends of the La Sal Avalanche Center. See our Sponsors Page for a complete list.