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

This morning, we have a CONSIDERABLE (L3) danger on any steep wind drifted slope in the higher elevations. They’ll be more pronounced on north through east through south facing slopes. Human triggered avalanches are probable. By midday, the danger will have dropped down to MODERATE (L2). Things will be less sensitive, but the potential to trigger a slide into the deeper weak layers will remain a distinct possibility.


CURRENT CONDITIONS

Good old fashioned cold front yesterday afternoon – heavy snowfall, strong and gusty winds, temps plunging to the single digits…….even a little thunder. Snow totals are up to 16” in Little Cottonwood, 8-10” in Big Cottonwood and the Park City mountains, perhaps 2-4” on the Ogden skyline but closer to 10” east of the mountain valleys, and about 3” in the Provo terrain. The snow fell “right-side-up” with densities diminishing during the storm, but one could roughly gauge it to be 6-8% smoke. The northwest winds blew 30-35mph with gusts to the 50s during, and just after frontal passage, but are now a more reasonable 15-20mph with gusts to the mid 20s. Skies are now partly cloudy to mostly clear. It’ll be one of those days.


RECENT ACTIVITY

We heard of no activity or mishap in the backcountry, but yesterday I took a look at the Saturday incident on Mt. Aire. I came away impressed that the injuries only included a couple broken ribs and a tibial plateau. I also came away with a lost ski with the skin on, intact. Take a look at the Incident Report.


THREAT #1

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

Still sensitive wind drifts will be hidden under the lower density snow that fell through the wee hours of the night. With crowds swarming into the backcountry, I’d expect to see a few triggered soft slabs up to 18-24” deep in the lee of the higher elevation ridgelines. Test slopes and cornice drops, ski and slope cuts will be effective observation and mitigating tools when safely practiced. Natural avalanches were noted during the height of the storm overnight…..but the overall trend will continue toward increasing stability in the storm snow.


THREAT #2

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

The fine print: We enjoyed a free lunch through mid-January with avalanches running in lockstep with the storms. Not so anymore. While the overnight storm snow and wind slabs will gain strength, they’re adding stress onto some weak layers just beneath the snow surface and the old sleeping facets and surface hoar from January 8. Even yesterday – before the storm – our forecaster in Logan remotely triggered a 1-3’ deep hard slab that collapsed a 6 inch thick rain crust onto the weaknesses below. This on a north and east facing slope at 8000’. I’m also concerned with the thin crust/facet sandwiches on the south and easterly facing slopes formed over the past week…as well as the outliers such as Mt. Aire. This terrain had the weakest snow I’ve seen from Ogden to Provo and everywhere in between.


THREAT #3

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

Give the growing cornices a wide berth. Use a knotted rope of parachute cord or a fancy cornice/block cord if looking to drop a larger cornice today. Make sure no one is beneath you on the slope.


MOUNTAIN WEATHER

Skies are clearing in the wake of the storm. Temps are in the single digits, and winds are northerly at 10-15mph with gusts to 20. The next brush by affects northern Utah Wednesday night followed by clearing skies and a warming trend into the early part of the weekend. The longer range forecast hints at something interesting a week out. Check our mid to late morning mountain weather forecast for more details.


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: 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 by clicking HERE

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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.