Uintas Avalanche Advisory

Forecaster: Craig Gordon

BOTTOM LINE

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


Danger Rose Tutorial

 

Above treeline the avalanche danger is MODERATE on slopes steeper than about 35 degrees, especially those with recent deposits of wind drifted snow and human triggered avalanche are possible.

At mid and lower elevations there may be a rogue wind drift or two, but with the lack of uniform snow cover the avalanche danger is generally LOW.


CURRENT CONDITIONS

 

What a difference a storm makes. Monday’s little system vastly improved the riding and turning conditions with 6”-8” of very light density cold smoke falling at the upper elevations. Trailhead elevations didn’t do too badly either, with about half that amount stacking up. High pressure building over the region created strong upper elevation northwest winds late yesterday and overnight. At most ridgetop locations northwesterly winds are fairly reasonable, blowing 15-30 mph. but it’s pretty ruthless up high, cranking in the 40’s and 50’s along the peaks. Current temperatures are slightly inverted- in the mid to upper 20’s at 10,000’ and upper teens at 8,000’.

 

 

 

 


RECENT ACTIVITY

A few natural soft slab avalanches were spotted on steep slopes like Double Hill as a result of Monday's storm.


THREAT #1

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

Fresh wind drifts formed along the leeward side of upper elevation ridges, chutes and gullies will be today’s most obvious avalanche concern. While pockety in nature, isolated to a small portion of the terrain out there and mostly manageable in size, these drifts will be sensitive to the weight of a person today and may pack a little more of a punch than you’d expect.  

 


THREAT #2

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

Whenever I go to a new mountain range I always ask the locals “what’s the winter been like?” My interested really piques when someone tells me they’ve never seen conditions like this before. So as I talk with riders who’ve been in the Uinta’s for generations and they tell me our current snowpack setup is something they’ve never seen before, I take notice. As we know, unusual snowpack and weather conditions make unusual avalanches.

Once again this year we’re faced with a complicated snowpack that will no doubt get extremely cranky once winter kicks into high gear. The very unusual Thanksgiving weekend rain crust has everyone concerned and for good reason. It seems this crust is strong enough to hold some additional snow weight, but fails on well developed weak sugary facets when we try to perform any snow stability tests. Big take home point here is that it's going to be dicey once it starts storming again.

While our snowpack adjusted rapidly to Monday’s light density snow, strong winds late yesterday and overnight created wind drifts in upper elevation, leeward terrain. While more the exception than the rule, I think you might be able to trigger avalanches in isolated areas today which have the possibility of breaking into weaker snow at or just below the rain crust, creating a larger avalanche than you might be prepared for.


MOUNTAIN WEATHER

 

High pressure slowly builds over the region today and tonight and this looks like the calm before the much anticipated stormy period. For today though, some mid and high level clouds drift through the area ahead of a weakening system slated to clip the state on Thursday. Winds are going to be an issue for most of the day, blowing 15-25 mph with gusts in the 50’s along the high ridges before relaxing later in the day. High temperatures will be in the low to mid 30’s. Overnight lows under mostly cloudy skies will be in the upper teens. A weak storm gives us light snow showers on Thursday followed by an in between day on Friday. The computer models advertise a series of cold storms nosing into the area starting on Saturday morning, bringing an extended period of unsettled weather to the region.

 

 


GENERAL ANNOUNCEMENTS

Remember- your observations help to save other riders lives. So if you see or trigger any avalanches please let me know what your seeing. You can reach me at 801-231-2170 or craig@utahavalanchecenter.org

While it's quiet, now is a great time to schedule a free avalanche awareness class for your group or club. You can reach me at 801-231-2170 or craig@utahavalanchecenter.org for more details.

The information in this advisory expires 24 hours after the date and time posted. I'll update this advisory by 7:00 am on Saturday Dec. 13, 2008.


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.