Avalanche Advisory
Advisory: Logan Area Mountains Issued by Toby Weed for Friday - February 21, 2014 - 7:00am
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In many areas the danger is Level 2 or MODERATE, with shallow wind slab avalanches possible, and you can find mostly stable snow conditions at lower elevations and in sheltered lower angled terrain in the Logan Area backcountry. But, there's still a CONSIDERABLE or Level 3 avalanche danger on steep drifted slopes at upper elevations and although the probability is decreasing, you might trigger very dangerous and destructive deep slab avalanches in steep terrain. Careful snowpack evaluation, cautious route-finding, and conservative decision making will be essential for safe travel in the backcountry today.




current conditions

The Logan Summit weather cam is showing snowfall this morning, and the 8400' Tony Grove Snotel reports a couple more inches of new snow containing 3/10ths of an inch of water overnight, bringing the last two day's accumulation up to about 6 inches. It's 20 degrees and there's 98 inches of total snow, containing 120% of average water content for the date. The 9700' CSI Logan Peak weather station reports 22 degrees and 30 mph average wind speeds from the southwest, with gusts over 60 mph this morning. Colder temperatures solidified the saturated weak snow at lower elevations, and you stay on top of a solidly refrozen crust in an inch or two of fresh snow from yesterday. Riding conditions up high are nice, but I'm still avoiding steep terrain due to widespread poor snow structure and the gradually diminishing chance that I could trigger an un-survivable avalanche.

Bruce Tremper just published a Storm Analysis Blog that explains aspects our recent active natural avalanche cycle. HERE And he explains this weekend's generalized snow situation well in this video



recent activity

It's been almost a week since our last reported avalanche activity in the Logan Zone.

Looking at a very large natural avalanche in Pine Canyon in the Wellsville Mountain Wilderness on 2-19-2014

***Video look at a HUGE natural avalanche in the Wellsville Range, from 2-19-2014...........HERE


Last week, in addition to numerous large natural avalanches in the backcountry, there were a few close calls with dangerous unintentionally triggered avalanches and another incredibly lucky survival story in the Providence Canyon Area, in which a rider was completely buried, rescued by his partners unconscious and unresponsive, but recovered and was able to ride out on his own....SEE REPORT

Check out "Beaver Backside is the Backcountry," an Avalanche observation video from 2-16-2014 .....HERE

A child's perspective on last week's natural wet avalanche above Zanavoo in Logan Canyon filmed on 2-17-2014 .......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 instability from last week's rapid loading appears to settling be out with time and it is increasingly unlikely the you would trigger one, but dangerous triggered deep slab avalanches failing on preexisting faceted weak layers at the bottom of the snowpack remain possible today, especially on drifted upper and mid elevation slopes that didn't naturally avalanche in the recent prolonged cycle. Drifted slopes with shallow overall snow cover are the most suspect, since shallow areas tend to harbor the weakest snow. Although ever more unlikely, you still might trigger dangerous avalanches remotely, from a distance or even from the flats below steep slopes in some cases.

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

Triggered wind slab avalanches are possible on steep slopes, and a smaller avalanche overrunning a slope with poor snow structure could cause a step-down into weak old snow and result in a much larger and more dangerous deep slab avalanche. Avoid stiffer drifted snow on the lee sides of major ridge lines and in and around terrain features like rock outcroppings and gullies.

weather

It's snowing this morning in the Bear River Range and more snow is likely today, with 1 to 3 inches of accumulation possible up high. Expect a high temperature of 27 degrees at 8500' and sustained and gusty southwest winds. Showery snowfall and southwest wind will continue overnight and tomorrow, with 3 to 9 inches of accumulation possible by tomorrow evening. We might see a bit of sunshine on Sunday.

Check out our one-stop weather page........HERE

general announcements

 Discount lift tickets are 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.

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

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.

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.