Salt Lake Avalanche Advisory

Forecaster: Brett Kobernik

SPECIAL ANNOUNCEMENT

A Special Avalanche Advisory remains in place through today. Strong winds and additional snowfall will create dangerous and widespread avalanche conditions. Human triggered avalanches are likely; natural avalanches possible. Backcountry travel requires cautious route-finding and conservative decision making.


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 is CONSIDERABLE on steep north through southeast facing slopes that have fresh wind drifted snow. Human triggered avalanches are probable and natural avalanches possible. The danger drops off dramatically out of wind effected terrain.


CURRENT CONDITIONS

Continued moderate to strong winds and higher density snow headline the advisory today. We picked up another 1 to 3 inches of higher density snow overnight bringing 48hr settled snow totals to 3 to 6 inches of 10% density snow. The winds increased in speed overnight with moderate to strong gusts, switching back and forth between southwest and northwest. A rime event occurred on Tuesday with many areas receiving a zipper rime crust. The snow was starting to feel inverted on Tuesday. The snow was damp below around 8500 feet.


RECENT ACTIVITY

Sensitive soft slabs were reported by most people who were out yesterday, some releasing remotely. These were generally fairly shallow and pockety but a couple were large enough to take a person for a ride with fracture lines up to 18” deep. Natural activity from early yesterday morning was noted as well. All the activity was mainly on the leeward northeast through southeast aspects but some on north as well. The lower density snow from Sunday was acting as the weak layer. Photo: Dog Lake Chutes near Brighton - Kobernik


THREAT #1

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

Fresh wind slabs will be the most active concern today. I suspect they won’t be as sensitive as on Tuesday but probably will be larger. Watch for cracking as you travel. This is an indicator you are in areas with a sensitive wind slab present. Northeast through southeast aspects are the most likely spots to find freshly drifted snow that could release under the weight of a person, especially along ridgelines.


THREAT #2

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

The next thing we need to think about is how the additional high density wind blown snow is effecting our buried persistent weak layers. Have we added enough weight to overload some of them? I can’t answer this for certain, therefore, I can’t justify getting onto steep slopes that have both 1) a buried persistent weak layer and 2) a fresh wind slab. Areas with a shallow overall snowpack such as slopes that have already avalanched this season or areas outside of the upper Cottonwoods where the pack is just generally thinner are the most suspect. I wouldn’t be surprised to hear about natural activity on a few of these


MOUNTAIN WEATHER

Scattered light snowfall is possible through this morning with continued strong northwesterly winds. Temperatures will remain very mild for most of today with the rain/snow line up around 7000 feet or a bit higher. Snow showers may pick up later this afternoon ahead of a cold front that moves through tonight which will produce a quick shot of snow with continued strong winds. We could pick up another 4 inches with a bit more in the upper Cottonwoods. Another storm is shaping up for the weekend.


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)

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

Twitter Updates for your mobile phone http://utahavalanchecenter.org/twitter)

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

Wasatch Powderbird Guides does daily updates about where they'll be operating on this blog http://powderbird.blogspot.com/ .

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

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.

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.