Salt Lake Avalanche Advisory

Forecaster: Drew Hardesty

SPECIAL ANNOUNCEMENT

Last minute Holiday gift? Alta ski area has generously donated lift tickets to support the Utah Avalanche Center. Backcountry.com generously administers everything else.

BOTTOM LINE

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


Danger Rose Tutorial

The danger is MODERATE for lingering storm snow avalanches up to a foot deep on all aspects. They’ll be more pronounced on the steeper east to south to westerly facing aspects. The soft slabs are likely to break at your feet or sled and will have been indicated by the snow pits that you’ve dug in nearby representative terrain.

MODERATE – Human triggered slides possible. Evaluate snow and terrain carefully.


CURRENT CONDITIONS

Apparently we’re going to see this great glowing orb in the sky today. It’s been a good run since last Friday afternoon. Snow-water-equivalent storm totals look to be roughly 9” in the Cottonwoods and parts of the Ogden mountains, 6 ½ -8” in the Park City mountains, and a near over-the-top 12 ½” of water weight in the Provo mountains. This all translates to roughly 50-80” of snow at the observations stations, with more in the highest terrain. I’m looking forward to getting up high on Timpanogos soon.

Winds are mostly calm, and temps are in the upper teens along the ridgetops with cooler air settling in the basins and drainages. Riding conditions are fair in the thick cement and best on a single plank with a decent pitch. Trail-breaking remains punchy and inverted.

RECENT ACTIVITY

We heard of no human triggered slides in the backcountry yesterday, though we did receive info on two naturals on the backside of the Wasatch Crest. The first in upper Snake Creek on an east southeast facing slope at 9300’ 18” deep and reported to be 500’ wide. The other in upper Bonanza Flats near the way southern end of the Park City ridgeline with a depth of 12”, and 40’ wide. These likely ran on the lighter density stellars underneath Wednesday night’s heavier snow. I’m still finding shears at this interface.


THREAT #1
WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

From 1922 to 1984, Elbert Despain delivered mail up Little Cottonwood Canyon and gained the distinction of being the oldest mail carrier in the United States. It must’ve been the exercise and clean air. Perhaps it was because he was in love with the mountains. But that’s not all. Gone-but- hardly-forgotten avalanche scientist Ed LaChapelle once asked Despain how he managed to miss getting caught in an avalanche all that time. He replied without hesitation, “After a heavy fall of new snow, wait two days.” I’m not sure the details on how Despain passed on into the next life. LaChapelle died of a heart attack skiing powder in Colorado.at the age of 81. Both lived long lives due to good judgement and discipline.

In the most simplistic terms, the past week of alternating waves of warm and cold fronts have cooked up what amounts to a layer cake of heavy and light density snow. We’re most concerned with the upper layer of 10-14” of heavy snow on the lower density stellars below. Due to temperature and pressure, they’re gaining strength – as is the entire snowpack – rapidly. There will, however, be a few localized storm snow slabs triggered on this layering today – and primarily by explosive control work – but not entirely. That’s why the danger is not LOW. Those that don’t “wait two days” may find this to be true.

THREAT #2
WHERE PROBABILITY SIZE TREND
      Over the next 12 hours.

It’s not cold smoke on a slick rain crust, but the direct sun and warm temperatures will lead to some pinwheeling and shallow push-a-anche sluffs during the heat of the day. Avoid the steepest sunny aspects by noon.

MOUNTAIN WEATHER

Clear as a bell above the valley fog. Winds will be light from the west with 8000’ and 10,000’ temps rising to 35 and 28 degrees, respectively. Christmas day will be the same but warmer – temps rising to the mid to upper 30s at 10,000’. A weakening storm moves through on Sunday with what looks to be a decent system mid-week.

GENERAL ANNOUNCEMENTS

If you trigger an avalanche in the backcountry - especially if you are adjacent to a ski area – please call the following teams to alert them to the slide and whether anyone is missing or not. Rescue teams can be exposed to significant hazard when responding to avalanches, and do not want to do so when unneeded. Thanks.

Salt Lake – Alta Central (801-742-2033)

Ogden – Snowbasin Patrol Dispatch (801-620-1017)

Provo – Sundance Patrol Dispatch (801-223-4150)

Discount Lift Tickets to benefit the UAC! 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.

Wasatch Powderbird Guides flight plan.

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

Daily observations are frequently posted by 10 pm each evening.

Subscribe to the daily avalanche advisory e-mail click HERE.

UDOT canyon closures UDOT at (801) 975-4838

You have the opportunity to participate in the creation of our own community avalanche advisory by submitting avalanche and snow observations. You can also call us at 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.

We will update this forecast tomorrow 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.