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

A MODERATE danger exists in the Wasatch. Human triggered avalanches remain possible. The danger is most pronounced in the steep high northerly and westerly wind loaded terrain and in the shady mid-elevations where we have reactive layers of surface hoar. Careful routefinding and terrain management is required.


CURRENT CONDITIONS

Skies are overcast with light snow falling in the high terrain. Add this to another trace to 3” yesterday. The southeasterly winds continued to punish both the snow and travelers in the high terrain yesterday, though it lost some of its steam as it veered southwesterly in the afternoon. Riding conditions remain excellent in the mid to high sheltered terrain of the Wasatch – otherwise it’s breakable crust or stout wind damage in much of the exposed periphery of the south and east side of the horseshoe that surrounds the Cottonwoods.


RECENT ACTIVITY

· Have I mentioned the strong southeasterly winds? They prodded natural activity on Saturday and again yesterday. We received reports of at least two naturals in the upper Wolverine/Pioneer environs of BCC breaking 14” deep and up to 80’ wide. Both steep loaded northerly terrain above 10,500’.

· On a 35 degree northwest facing slope just outside of Summit Park in Parley’s canyon, a ski party remotely triggered a 16-24” soft slab on the Feb 10 layer of surface hoar. Elevation band was at 7800’. The slab propagated 125’ wide, running 200’ down the slope.

· A skier near Soldier Fork of Mill Creek remotely triggered a soft slab perhaps up to 18” deep and 100’ wide. The slide was on a northwest facing slope at 8800’.

· A skier was carried 100’ down a steep rocky chute above the Argenta slide path of Kessler Peak yesterday and is reportedly ok. The foot deep soft slab broke above him in the rocks and had nowhere to go but down. Glad all’s well.

· Details are sketchy but we’ve received a report of a full burial and recovery of a skier yesterday in the Uintas. Craig Gordon will have more details on this by the afternoon.

More details, pics, and more can be found in the upper left hand corner of the page under Current Conditions.


THREAT #1

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

Lingering wind slabs remain in the higher lee terrain and on steep rollovers and gulley sidewalls. Avoid the fat pillowy rollovers – remember that the stronger winds loaded areas half-way down the slope and in unusual areas. The loading is most pronounced in the upper reaches of the Cottonwoods, along the AF ridgeline, and along the southern end of the Park City ridgeline.


THREAT #2

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

Here are the facts: We continue to have avalanches onto the February 10th and 17th layers of buried surface hoar. They’re buried 16-24” deep, continue to be triggered at a distance, and may break way above you. This tricky weak layer is most widespread on mid elevation, northwest through northeast facing slopes, and most pronounced in terrain north and east of Big Cottonwood canyon. This is what we call Bull’s Eye Information. Critical.

Here’s the unsettling part: The surface hoar is variable across the terrain and our so-called snowpit tests are even more variable. To wit: our tests adjacent to Saturday’s slide in West Porter Fork of Mill Creek produced a reluctant failure plane – on the surface hoar beneath the avalanche’s bed surface. Sure, the overlying slab is gently stabilizing the surface hoar layers (more with my observation from yesterday), but this can be perhaps arguable and distracting to the matter at hand. One can look at grain size, thickness, depth, temperature, etc, etc but – Keep it simple. Know where the surface hoar layer’s habitat is and either avoid it, or keep your slope angles down.


MOUNTAIN WEATHER

Unsettled weather today with a trace to two expected. Winds will be generally light from the west-northwest. Temps will be in the low 20s. The main storm dives south tomorrow with a second storm possible for Wednesday night into Thursday.


GENERAL ANNOUNCEMENTS

SLC: Please contact Alta Central (801-742-2033) if you trigger a large avalanche in the backcountry, especially if you are adjacent to a ski area, 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.

Ogden: Please contact Snowbasin ski patrol (801620-1000/1017) if you trigger a large avalanche in the backcountry, especially if you are adjacent to a ski area, 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.

Provo: Please contact Sundance ski patrol (801 -223-4150) if you trigger a large avalanche in the backcountry, especially if you are adjacent to a ski area, 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.

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.

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.

Free UAC iPhone app from Canyon Sports.

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

UDOT canyon closures UDOT at (801) 975-4838

We appreciate all your avalanche and snow observations. You can also call us at 801-524-5304 or 800-662-4140, or fill out the observation form on our home page.

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.