Logan Avalanche Advisory

Forecaster: Toby Weed

SPECIAL ANNOUNCEMENT

The Utah Avalanche Center in Logan and Renegade Sports are teaming up to offer a FREE Avalanche Beacon Training Clinic on Tuesday, February 23rd from 5-7pm at Renegade Sports in Nibley. The clinic is open to everyone who wants to learn how to properly use an avalanche rescue beacon. Bring a friend or your family or your scout troop! It is an open house so come when you can. Remember, it's FREE and what you learn may save your life or the life of someone you know. For more info call 755-7111 or 757-2794.


BOTTOM LINE

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


Danger Rose Tutorial

There's a MODERATE (2) or elevated avalanche danger on many slopes in the backcountry, but a CONSIDERABLE (3) danger exists in some upper and mid elevation areas, and you still might trigger a very dangerous deep slab avalanche. Dangerous avalanche conditions persist, particularly in steep terrain with shallow overall snow-cover and where weak sugary snow plagues the basal layers of the snowpack. The danger of deep slab avalanches appears to be greatest and recent large natural avalanches have occurred on upper elevation northwest, west, and southwest facing slopes. Also, pockets with a CONSIDERABLE (3) danger remain and triggered avalanches around a foot deep are possible on shady and sheltered upper and mid-elevation slopes approaching or steeper than about 35 degrees. You'll find safer conditions this weekend at lower elevations and on lower angled slopes.

Careful snowpack evaluation, cautious route-finding and conservative decision-making are essential for safe backcountry travel this weekend.


CURRENT CONDITIONS

A thin rime-crust formed by low clouds on Wednesday, and now capped by an inch or two of light snow is fairly widespread across the zone. Snow surface conditions can’t quite be described as powder anymore, but you can still find good soft conditions especially in the trees. With about an inch of snow in the past 24 hours, there's now 74" of total snow on the ground at the Tony Grove Snotel containing 69% of average water for the date. Its 3 degrees at the 9700' Campbell Scientific--Logan Peak weather station and a very light wind is currently out of the north, averaging less than 5 mph.


RECENT ACTIVITY

Yesterday was quite active in the Wasatch Range backcountry, with at least 10 more human triggered avalanches involving around a foot of recently accumulated snow failing on a weak layer made up of feathery 2 dimensional frost crystals or small sugary grains, which is widespread across the region.

Locally; numerous avalanches were reported across the forecast zone in the last week..By far the vast majority of these involved the newest snow picked up since a nice layer of surface hoar was covered and preserved by light snow on Wednesday 2-10-10. A few very large natural deep slab avalanches became visible with brief clearing on upper elevation west facing slopes in the Mount Naomi Wilderness.

Here's an updated local backcountry avalanche list:


THREAT #1

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

Weak sugary or faceted snow near the ground is notoriously slow to heal, and recent natural deep slab activity in the zone proves that a brood of dragons is still hanging around. I'm particularly concerned by huge recent natural deep slab avalanches on upper elevation west facing slopes in the Mount Naomi Wilderness ..(Water Canyon 2-13-2010). (Cougar Peak 2-19?-2010)

Although the danger of deep slab avalanches is gradually diminishing, in some areas you still might trigger a dangerous avalanche from a distance or from below. Triggered deep slab avalanches could step down to weak snow near the ground and be very broad and destructive. Deep slab avalanches might be initiated from a shallower area on the slab, so watch out for steep rocky or terrain with generally shallow snow cover. Direct solar heating or green-housing, (with clouds and sunshine) may increase the creep rate of softening slabs, causing very large avalanches to be more likely on some slopes...


THREAT #2

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

A weak layer consisting of surface hoar or frost, buried under a foot or so of snow, is widespread across the region.....We've observed numerous triggered and natural avalanches on this persistent buried layer recently, and some of these avalanches occurred on fairly low angle slopes. The weakness is stabilizing gradually, which may actually make the situation more dangerous because slopes may allow you to get out on them before releasing...


MOUNTAIN WEATHER

Light snowfall will resume in the mountains today and continue through most of the weekend, but accumulations will be on the light side and winds should also stay fairly light. Our best chance for more than flurries comes tomorrow, and we might pick up a couple inches of accumulation... Expect generally dryer conditions, with a building high pressure and only weak splitting storms next week....


GENERAL ANNOUNCEMENTS

I will be issuing morning avalanche advisories for the Logan area on Mondays, Wednesdays, Fridays and Saturdays.

Consider purchasing some Beaver Mountain lift tickets here from our good friends at Backcountry.com in partnership with Ski Utah. All proceeds benefit the Friends of the Utah Avalanche Center.

If you want to get this avalanche advisory e-mailed to you daily click HERE.

Send us your avalanche and snow observations. You can also call me at 435-757-7578 or the SLC office at 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.

I will update this forecast Monday morning. Thanks for checking in....


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.