Avalanche Advisory
Advisory: Logan Area Mountains Issued by Toby Weed for Friday - December 27, 2013 - 7:06am
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Dangerous avalanche conditions exist in the backcountry, and there is a Level 3 or CONSIDERABLE danger on drifted upper elevation slopes. Dangerous persistent slab and wind slab avalanche conditions exist in the Logan Zone at upper and mid elevations due to recent slab development and very weak preexisting faceted snow. You could trigger avalanches remotely, from a distance or below. Careful snowpack evaluation, cautious route-finding, and conservative decision making will be essential for safe travel in the backcountry.




special avalanche bulletin

THIS SPECIAL AVALANCHE ADVISORY IS FOR THE MOUNTAINS OF NORTHERN UTAH TO INCLUDE THE WESTERN UINTAS. DANGEROUS AVALANCHE CONDITIONS EXIST IN THE STEEP WEST TO NORTH TO EAST FACING TERRAIN. HUMAN TRIGGERED AVALANCHES 1-3 FEET DEEP ARE LIKELY. THIS SPECIAL AVALANCHE ADVISORY WILL CONTINUE THROUGH THE WEEKEND.
special announcement

Sign up now for our Avalanche 101 course to be held in Logan on January 9 and 11................. Information and registration
current conditions

The Tony Grove Snotel at 8400' reports 31 degrees this morning, and there is 35 inches of total snow containing 71% of average water content for the date. The 9700' Logan Peak weather station reports 28 degrees and west northwest wind, currently averaging in the upper teens. You can find pretty nice shallow powder conditions, but you tend to break through a brittle rime crust buried under a few inches of fresher snow from early Christmas Eve. Westerly winds scoured the fresh snow and the translucent crust is now on the surface on the ridges and exposed south and west facing slopes, making for tricky traveling in places. You'll still find dangerous avalanche conditions in many areas at upper and mid elevations in the Logan Area backcountry.

Looking at the range from the Cornice Ridge Area on 12-26-2013.

Here's a short video clip observation showing snow conditions and a natural avalanche in the Steep Hollow Area on 12-24-2013...... HERE
recent activity

The first two avalanche fatalities of the season occurred yesterday near Jackson Wyoming.... A backcountry snowboarder and a snowmobiler in separate incidents.

A fairly widespread natural avalanche cycle occurred in the Central Bear River Range as an energetic cold front passed through the region early Christmas Eve. The hard and soft slab avalanches occurred on northwest, north, northeast, east, and southeast facing slopes above around 8200' in elevation. They ranged from fairly small (around a foot deep and 30' wide) to pretty big, like the one on Cornice Ridge that was 2 to 3 feet deep and around a 1/4 mile wide...

Here's a look at a section of the broad crown of a natural avalanche on Cornice Ridge that occurred early Christmas Eve.

A video look at the Cornice Ridge Avalanche from 12-26-2013 observation......... HERE
Avalanche Problem 1
type aspect/elevation characteristics
LIKELIHOOD
LIKELY
UNLIKELY
SIZE
LARGE
SMALL
TREND
INCREASING DANGER
SAME
DECREASING DANGER
over the next 24 hours
description

The new snow from just before Christmas piled up and was drifted onto preexisting very weak sugary or faceted snow, which is widespread in the region, creating a slab layer on many slopes. Dangerous human triggered avalanches failing in old weak faceted snow or in the basal layers of the existing snow pack remain likely, especially in drifted upper elevation terrain You could trigger persistent slab avalanches remotely or from a distance, or worse, from below. Collapsing and/or shooting cracks are obvious red flags requiring you to reevaluate your route.

Avalanche Problem 2
type aspect/elevation characteristics
LIKELIHOOD
LIKELY
UNLIKELY
SIZE
LARGE
SMALL
TREND
INCREASING DANGER
SAME
DECREASING DANGER
over the next 24 hours
description

Subsequent drifting of last weekend's snow caused the development of wind slabs, in many cases on top of very week preexisting snow. Dangerous wind slab avalanche conditions exist in exposed upper elevation terrain. Triggered wind slab avalanches remain likely on steep slopes with significant recent deposits of drifted snow. You'll find wind slabs composed of stiffer snow in exposed lee slope terrain, especially in and around terrain features like gullies, scoops, sub-ridges, rock outcroppings, and cliff bands. We recommend that you avoid travel in steep drifted terrain.

weather

A high pressure system will move in overhead and take full control of the weather for at least the next few days, with fair and mild weather in the mountains and thickening valley inversions. There is a slight chance for a little snowfall before the New Year (Monday night and Tuesday) but don't expect much in the way of accumulation in the mountains or in scouring the smog from the valleys

Check out our one stop weather page........HERE
general announcements

The Utah Avalanche Center wishes you a safe and powder-filled holiday season. Please consider the UAC in your holiday giving plans - your donations pay for these advisories and we can't do this without your help.  What is it worth to you every day to get an avalanche and mountain weather advisory?  The cost of a beverage or the gas it takes to get up the canyon?  You can donate here.

Utah Avalanche Center mobile app - Get your advisory on your iPhone along with great navigation and rescue tools.

Discount lift tickets are now available at Backcountry.com - Thanks to Ski Utah and the Utah Resorts, including Beaver Mountain.  All proceeds go towards paying for Utah Avalanche Center avalanche and mountain weather advisories.

Benefit the Utah Avalanche Center when you shop from Backcountry.com or REI:  Click this link for Backcountry.com or this link to REI, shop, and they will donate a percent of your purchase price to the UAC.  Both offer free shipping (with some conditions) so this costs you nothing!

Benefit the Utah Avalanche Center when you buy or sell on ebay - set the Utah Avalanche Center as a favorite non-profit in your ebay account here and click on ebay gives when you buy or sell.  You can choose to have your seller fees donated to the UAC, which doesn't cost you a penny.

Remember your information can save lives. If you see anything we should know about, please participate in the creation of our own community avalanche advisory by submitting snow and avalanche conditions. You can also call us at 801-524-5304 or 800-662-4140, email by clicking HERE, or include #utavy in your tweet or Instagram.

Sign up early for one of our life-saving avalanche classes.......HERE           And refresh your avalanche knowledge, check out some of our tutorials........HERE

Follow us at UAClogan on Twitter 

I'll issue these advisories on Monday, Wednesday, Friday, and Saturday mornings. 

This advisory is produced by the U.S.D.A. Forest Service, which is solely responsible for its content. It describes only general avalanche conditions and local variations always exist.