Logan Avalanche Advisory

Forecaster: Drew Hardesty

AVALANCHE WATCH »

The risk of an avalanche is expected to increase significantly but the timing and location are still uncertain. Stay tuned for updates.
Notice:

THIS AVALANCHE WATCH IS FOR THE MOUNTAINS OF NORTHERN AND CENTRAL UTAH, TO INCLUDE THE BEAR RIVER RANGE, THE WESTERN UINTAS, THE WASATCH RANGE, AND THE WASATCH PLATEAU. FORECASTED STRONG WINDS AND HEAVY SNOWFALL WILL LEAD TO DANGEROUS AVALANCHE CONDITIONS. A CONSIDERABLE AVALANCHE DANGER WILL LIKELY RISE TO HIGH WITH NATURAL AVALANCHES LIKELY.


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 CONSIDERABLE. Human triggered slides are probable in ALL steep wind drifted terrain at a variety of aspects at the mid and upper elevations. These will be most pronounced on northwest through north through easterly facing slopes and prominent in the upper reaches of Big Cottonwood Canyon and along the Park City ridgeline. Any triggered slide has the capacity to step down 2-3’ deep onto the weaknesses adjacent to last week’s dust layer.


CURRENT CONDITIONS

A strong Pacific storm is on the doorstep. Moisture streaming in ahead of the core from the southwest has 8-10” of inverted snow already in the Park City mountains and in the upper reaches of Big Cottonwood canyon. Ogden, Provo and Little Cottonwood have 2-4” by press time. They’ll catch up in a hurry. No one, however, has been spared the wind. The southerly winds are blowing 35-45mph with gusts near 80 along the more exposed ridges, but lower elevations and otherwise generally protected areas are seeing wind damage as well. Temperatures are in the mid to upper 20s. The cold front looks to crash through the Wasatch by late afternoon accompanied by lightning and 2-3”/hour snowfall rates.


RECENT ACTIVITY

By now most of you are probably aware of the avalanche fatality up near Francis Peak along the Bountiful skyline. Details are thin at this time, but reports have the victim a local 42 year old snowmobiler. Our condolences to the family and friends.

Yesterday’s low density 6-8” of fluff proved quite sensitive to human provocation and everyone reported seeing and triggering the mostly harmless shallow sluffs and soft slabs. The high snowfall rates contributed to a shallow natural cycle in the early morning. We heard about two other slides in the backcountry – the first a remotely triggered slide above Butler Fork of BCC where a skier triggered a foot deep 30’ drift, a lingering pocket from Saturday’s winds. Just up the street along the Park City ridgeline, a touring party remotely triggered a cornice into West Monitor, triggering a hard slab pocket 2’ deep and 40’ wide onto the dust layer from last Tuesday. Control work in upper Little Cottonwood pulled out a 3-5’ pocket 200’ wide – similar to the significant control work from the Ogden mountains the day before. With enough snow and wind, these may be a portent of things to come….


THREAT #1

WHERE PROBABILITY SIZE TREND
      Over the next 12 hours.

New and inverted (aka – upside down) storm snow combined with winds will easily overload yesterday’s 5-7% density fluff. I expect any steep wind loaded terrain to be quite sensitive today to human weight. The strong southerly winds will load unusual terrain features, including mid-slope breakovers and drive crossloaded snow into gullies and lee encatchment zones. Growing cornices will be sensitive along the ridgelines. Test slopes will be the giveaway for evidence of instability. Remote triggering is a distinct possibility today.


THREAT #2

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

Any slide triggered in the mid and upper elevations may have the capacity to step down to weaknesses adjacent to last week's dust layer. (slide from west monitor) These will be stubborn, but potentially lethal if and when triggered.


MOUNTAIN WEATHER

We’ll have some intermittent snow through the day ahead of a strong cold front expected by about 5pm. Strong south to southwest winds will continue to precede the front, blowing 30-40mph with gusts into the 50s and 60s. Temperatures will be in the mid to upper 20s, then crash down again to the upper single digits by tomorrow morning. Heavy snowfall is expected during and after the front with 16-24” expected with up to 30” expected in favored terrain. Snow continues into early Wednesday with clearing skies and rapid warming by Thursday.


GENERAL ANNOUNCEMENTS

The ability to deal with medical emergencies is a vital backcountry travel skill. On April 9-11, Utah Wilderness Safety will be conducting a Wilderness & Remote First Aid course in SLC. As an added bonus, WMS has agreed to donate a percent of the class proceeds to the FUAC. For more details, go to our events calendar or www.utahwildernesssafety.com/FIRST-AID.html.

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 and the local resorts donated lift tickets, with 100% of the proceeds going to the Utah Avalanche Center. To get the last few tickets left for Park City, Beaver Mountain, and Sundance – click here 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.

Brett 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.