Avalanche Advisory
Advisory: Uintas Area Mountains Issued by Craig Gordon for Saturday - December 21, 2013 - 6:37am
bottom line

Terrain to avoid- steep, mid and upper elevation slopes in the wind zone, particularly those facing the north half of the compass, where a HIGH avalanche danger exists and human triggered avalanches are very likely. Once initiated, today's avalanches will break deep and wide creating an unmanageable and dangerous slide.

A MODERATE avalanche danger is found on upper elevation south facing terrain and human triggered avalanches are possible on any steep, wind drifted slope.

If you're looking for LOW avalanche danger, head to low elevation terrain which had very little snow prior to this weeks big storm




special avalanche bulletin

THIS SPECIAL AVALANCHE ADVISORY IS FOR THE MOUNTAINS OF NORTHERN UTAH TO INCLUDE THE WESTERN UINTAS. DANGEROUS HUMAN TRIGGERED AVALANCHES MAY BE TRIGGERED IN STEEP WEST TO NORTH TO EAST FACING TERRAIN ABOVE 8000` IN ELEVATION. EXPERT ROUTE-FINDING IS REQUIRED FOR SAFE TRAVEL IN THE MOUNTAINS. THIS SPECIAL AVALANCHE ADVISORY WILL CONTINUE THROUGH THE WEEKEND. THIS ADVISORY DOES NOT INCLUDE SKI AREAS OR HIGHWAYS WHERE AVALANCHE CONTROL IS NORMALLY DONE.

special announcement

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.

current conditions

Light snow is beginning to develop this morning as the next in a series of storms slides through the region. West and northwest winds are blowing 25-35 mph along the ridges with a gust or two in the mid 40's near the high peaks. It's a bit crisp this morning with temperatures hovering in the low teens. Thursday's storm delivered a foot of snow, vastly improving the riding and turning conditions. Mid and low elevation wind sheltered terrain is the ticket today.

Click here for current winds, temperatures, and snowfall throughout the range.

Click here for trip reports and avalanche observations.

recent activity

A sled triggered slide near Lake Creek yesterday, broke to old snow near the ground. Fortunately, quick reaction time and a successful airbag deployment lead to a happy outcome with this rider coming out on top of the debris.

Here's a first hand account- " I was sidehilling when the avalanche broke above me. It took me off my sled and within two seconds it completely came over my head and I immediately pulled the rip cord and within two seconds my head and shoulders were out of the snow but my waist and legs were trapped."

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

Winds are beginning to increase and there's no shortage of light density snow available to blow around and form wind drifts sensitive to the weight of a rider. This is a manageable avalanche problem because the shallow slabs break at or below our skis, board, or sled. But don't get lulled into thinking this is the only avalanche dragon we're dealing with this weekend. Underneath these fresh drifts is a dense cohesive slab, and it's resting on a very weak snowpack, especially on mid and upper elevation slopes facing the north half of the compass. These are the kind of conditions where most avalanche accidents occur because the snow we're riding on feels strong and solid. It allows us to get well out onto the slope before we collapse the hill (whoomph), trigger the slab, and now we're staring down a dangerous slide that's breaking deeper and wider than we expected, taking out the entire seasons snowpack as the avalanche slams us into rocks and trees.

Making matters more complicated is the fact that the region didn't experience a widespread natural avalanche cycle. So you're not going to be looking around staring at big, tree snapping avalanches. Nope... many slopes remain in the balance, just waiting for a trigger to come along and knock the legs out from underneath. What's going to make things more tricky today is, you'll be able to trigger avalanches from a distance and on relatively flat terrain, so you need to consider what type of terrain you're connected to. In other words, what steep slopes are above and adjacent to where you're riding.

Today you'll need to tone down your objectives and think about the consequences of triggering a slide. It doesn't mean you can't ride. In fact, you can have a blast on low angle slopes with no steep terrain above or adjacent to where you're riding.

We experienced large, booming collapses yesterday on relatively low angle terrain.... a huge red flag. Here, Trent points to the culprit- a layer of midpack facets formed during the very cold spell the first week of December.


weather

Light snow develops this morning and should linger through most of the day with 4"-8" expected by about dinner time. Northwest winds are gonna be a nuisance, blowing in the 30's and 40's with gusts in the 50's along the high peaks. High temperatures barely climb much higher from where we're at this morning, before crashing to near zero tonight. Partly cloudy skies are on tap for Sunday with a series of weak disturbances scheduled to graze the region through Wednesday.

general announcements

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 call me directly at 801-231-2170, email [email protected], or email by clicking HERE

This is a great time of year to schedule a free avalanche awareness presentation for your group or club. You can contact me at 801-231-2170 or email [email protected]

Donate to your favorite non-profit –The Utah Avalanche Center. The UAC depends on contributions from users like you to support our work.

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.

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

The information in this advisory is from the US Forest Service which is solely responsible for its content. This advisory describes general avalanche conditions and local variations always occur.

I will update this advisory by 7:00 AM on Saturday Dec. 21, 2013