Salt Lake Avalanche Advisory

Forecaster: Drew Hardesty

BOTTOM LINE

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


Danger Rose Tutorial

The avalanche danger remains MODERATE with pockets of CONSIDERABLE on steep westerly to northerly to easterly facing slopes along the mid and upper elevations.The danger is exclusively for slopes that have not avalanched since the December 13th storm. Experience, caution, and a healthy skepticism remain requirements for the backcountry.


CURRENT CONDITIONS

Skies are clear, but the southerly winds picked up a bit around midnight. Exclusively along the uppermost exposed ridgelines, they’re blowing 20-25mph with gusts to near 30. They’re mostly calm along the more sheltered terrain and I don’t expect them to last long up high. Temps are bottoming into the single digits up high and down low while the thermometers along the thermal belt are in the mid to upper teens. Riding conditions are not bad on the recycled, recrystallized snow in the sheltered mid-elevations.


RECENT ACTIVITY

Details are filtering in of a close call on the western flank of Box Elder Peak from Saturday. A very experienced skier in a party of four collapsed a mid-elevation slope, triggering a 3’ deep and 150’ wide hard slab that pulled out to near the ground. Breaking 15’ above him, the “washing machine-sized blocks” knocked the skier down and lost a ski, but he apparently was not buried nor did he sustain any injuries. Of equal interest was the reported aspect (northwest-southwest) and elevation (8500’). It’s possible that the skier found a thin, rocky weak spot that had a thin layer of old faceted pre-existing snow. I’ll hope to have more details later.


THREAT #1

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

Saturday’s skier triggered slide (along with another, slightly older slide up along the Cornice ridge in the Logan area mountains) offer verification of the hazard in the backcountry: Steeper terrain that did not slide two weeks ago during the storm is still hanging in the balance.

Collapsing of the myriad basal weaknesses are less frequent – the exception now rather than the rule. Snowpack tests indicate a strengthening overlying slab and a slow to strengthen - if not regressing - complement of weakening faceted snow below. My own analysis produces inconsistent full propagation scores on the Extended Column Tests. With this type of avalanche phenomenon (it’s like a backcountry vacation to Colorado w/o ever having to leave your own range) one must weigh the red flag stability scores and discount the others.

Those skiing and riding in the steeper terrain are putting in the time, homework, and continual route-finding to discern those slopes that have avalanched and those that haven’t. It’s not guesswork or intuition. In my book, intuition should be used as a red flag and not a green light. Otherwise, it’s just a roll of the dice.


MOUNTAIN WEATHER

Should be another nice day in the hills. Winds will be light from the south, temps will be in the mid-20s at 8000’ and the upper teens at 10,000’. Increasing clouds this afternoon precede a sad looking split system for tomorrow with a better looking storm for Wednesday. 4-8” likely for the second wave, with unsettled if unimpressive features set for the rest of the week and into the weekend.


GENERAL ANNOUNCEMENTS

Discount Lift tickets: Ski Utah, Backcountry.com, Alta, Deer Valley, Park City, The Canyons, Wolf Mountain, Snowbasin, Beaver Mountain, Brighton, Sundance, and Solitude have donated a limited number of tickets for sale at discounted prices.

For the Wasatch Powderbird Guides schedule go to their blog

Dawn Patrol Forecast Hotline, updated by 05:30: call 888-999-4019, option 8,

Daily observations are frequently posted by 10 pm each evening.

You can get a free iPhone application from Canyon Sports to display the Bottom Line.

To get a daily avalanche advisory e-mail click HERE.

For a text only version click the upper left link under Search

For canyon closures call UDOT at (801) 975-4838

Send us your avalanche and snow observations. You can also call 801-524-5304 or 800-662-4140, or email to uac@utahavalanchecenter.org

Donate to your favorite non-profit – The Friends of the Utah Avalanche Center. The UAC depends on contributions from users like you to support our work.

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 forecast on Tuesday morning. Thanks for calling.


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.