Ogden Avalanche Advisory

Forecaster: Drew Hardesty

SPECIAL ANNOUNCEMENT

Written with the help of Don Sharaf, longtime avalanche professional and colleague from the Tetons. Thanks for his help -

BOTTOM LINE

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


Danger Rose Tutorial

Pockets of Considerable danger dot the landscape in an overall MODERATE backcountry. Sensitive soft slabs of up to 2' deep remain in these mid-elevation NW through NE aspects on slope angles as low as 30 degrees. Most but not all of the wind drifts from Saturday have settled out - still - watch for and avoid any pillowed drifts in the higher lee terrain. Warm temperatures, light winds, and clear skies will allow for rapid heating of the solar aspects - east through south to west as the sun follows the compass on the first day of March.

CURRENT CONDITIONS

Written with the help of Don Sharaf, longtime avalanche professional and colleague from the Tetons. Thanks for his help -

RECENT ACTIVITY

Yesterday saw fewer human triggered slabs than days past. Wind slabs formed on Saturday morning at ridge crests continue to be ski cut on northerly- facing terrain above 9500' up to 18" in depth and 50' wide. One noteworthy result was at 9800' in upper American Fork. The buried surface hoar layer(s) continues to produce clean shears in stability tests (note ob here) and failed 10"-20" deep at 8600' (N to NE) on a ski cut in the Maybird Aprons area in Little Cottonwood Canyon. The top of this avalanche was 250' down from the ridge-crest and was likely sniffed out by an observer who was wary of the pockety (some might say "random") distribution of the buried surface hoar in Little Cottonwood Canyon.

We have also received several observations with "pertinent negatives." Sounds like an oxymoron, or political psycho-babble, but when you are trying to figure out stability patterns from a carpeted cube, it is as important to hear about where the snow is NOT reactive to slope cuts, and riding, as it is hearing about the action spots... keep those obs coming.

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

Bluebird skies with light winds are beckoning! Mid elevation shaded aspects are riding well and are not giving easy clues to the instability that lurks 12 to 24" below the surface. The surface hoar continues to be remotely triggered on occasion, but sometimes waits for the second or third skier before it gives up its battle between compressive strength and weakness in shear. Upper elevation northerlies have more recently formed wind slabs that could step down to the buried surface hoar making for higher volume (and potentially higher speed) avalanches. The surface hoar typically does not form under the evergreens and the snow remains delightful on shaded tree runs.

THREAT #2
WHERE PROBABILITY SIZE TREND
      Over the next 48 hours.

The wind slabs that formed from the S/SW winds on Friday night and Saturday morning are aging and becoming far less reactive than they were on Saturday. There were some reports of productive ski cuts up to 18" deep and 50' wide, though we're not ready to write them off. Exposed areas above 9500' that show eroded tracks, or surfaces, on the windward side and smooth pillows on the leeward are areas to be wary of. If the snow is firm enough so that your board(s) only penetrate an inch or two, then there is a potential for a hard slab surprise (think and act accordingly). Wind loaded slopes greater than 35 degrees are the most likely habitat to find these wind slabs. Ski cuts may be effective on the 2 day old wind slabs at ridge crest, but some of our persistent slab activity is occurring mid-slope and is less predictable in where fractures may occur.

THREAT #3
WHERE PROBABILITY SIZE TREND
      Over the next 12 hours.

The third day of comparatively warm temperatures will produce more wet loose slides particularly on high angle terrain (35 degrees plus), especially adjacent to exposed rock/cliffs. These avalanches shouldn't be too hard to predict, nor avoid. Be cautious in steep terrain where the wet loose oozers could push you somewhere you don't want to be.

MOUNTAIN WEATHER

Warm, sunny, and light winds - a fine way to start off March. Temps at 8000' will approach 40 degrees F and ridge tops should be in the upper 20's.

Winds should be on the increase from the south tomorrow afternoon as the clouds build. A weak storm will approach over Northern Cali/Southern Oregon, which has the possibility of dropping about an inch of moisture by midnight on Thursday. A short break between storms on Friday with another 1" shot on Friday night and Saturday. Stay tuned for the tomorrow's update of "As the model runs..."

GENERAL ANNOUNCEMENTS

Please contact Snowbasin snowsafety (801)-620-1017/1000 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 email to uac@utahavalanchecenter.org

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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.