Avalanche Advisory
Advisory: Logan Area Mountains Issued by Toby Weed for Saturday - November 21, 2015 - 7:11am
bottom line

There's a CONSIDERABLE (level 3) danger at upper elevations in the backcountry, and dangerous avalanche conditions exist, especially on drifted slopes. You are likely to trigger dangerous persistent slab avalanches on slopes steeper than about 35 degrees. Heightened conditions exist in drifted mid-elevation terrain as well, and shallow snow conditions mean a ride in any avalanche could be traumatic, with rocks and down trees adding to the danger. Avoid steep, previously drifted terrain and use wise travel protocols.
special announcement

Join us for a free avalanche awareness talk with the USU Outdoor Recreation Program at 7:00 on December 1

Don't miss the 12th annual Utah Avalanche Center in Logan's "Pray for Snow" party and fundraiser, the evening of December 3, again at the Italian Place in Downtown Logan.. For info and tickets go ............HERE

current conditions

Heavy snow and strong, sustained westerly winds Thursday and Thursday night created dangerous avalanche conditions at upper elevations. The Tony Grove Snotel at 8400' reported 11" of new snow containing 2.4" of water equivalent from the storm, and there's 21 inches of total snow containing 93% of average water for the date. The CSI Logan Peak weather station at 9700' reports diminished north west winds overnight, currently westerly, averaging in the low teens. It's 9 degrees on Logan Peak and 14 at Tony Grove this morning. Observers report triggering numerous audible collapses yesterday in the Tony Grove Area, and my party also did on Beaver Mt. indicating unstable snow.


Greatly improved coverage, but dangerous avalanche conditions at upper elevations in the Tony Grove Area yesterday. (Pagnucco 11/20/15)

​Words of warning: Very shallow, early season conditions exist, and you are still likely to hit rocks or woody debris in most areas. The Tony Grove Road is not maintained in the winter for wheeled vehicles, and road conditions are icy, snowy, drifted-in and treacherous, so come prepared. The upper section of the road and the loop at the lake were impassible yesterday. The Tony Grove Area is a shared use area and very popular in the early season, so please watch your speed, use patience, and be respectful of other users.

It's time to dust off and check the condition of your avalanche rescue equipment. Review and practice Companion Avalanche Rescue with our video..........HERE****

recent activity

Observers report spying two fresh natural avalanches off Cornice Ridge yesterday. These (seen from a distance) on a generally east facing slope appeared to involve new snow and ran from ridge (~9400') to bench around 500 vertical feet.

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

Strong southwest winds accompanied the recent heavy snowfall, and significant drifting resulted. The shallow snow on the ground for the past couple week's has become faceted and weak due to a strong temperature gradient. Thick slabs build on this very weak sugary snow and the persistent instability will last for a while, only gradually stabilizing. Reports of audible collapsing confirm the existence of unstable snow, (weak sugary snow on the ground and heavy fresh snow creating a slab on top). Suspect drifts on the lee side of ridge lines and terrain features where drifted snow was deposited like gully walls, cliff bands, mid-slope roll-overs, scoops. Avoid recently drifted snow on steep slopes... Due to the shallow snow conditions, a ride in even a small avalanche could be traumatic.

weather

Expect fair and clear weather through the weekend and into early next week. It'll be sunny in the mountains today, with 8500' high temperatures around 31 degrees and west winds less than 10 mph on the ridges. It'll be clear tonight, with low temperatures around 15 degrees. A "long duration" period of snowy and unsettled weather is expected in the days around the Thanksgiving holiday....
general announcements

Please submit snow and avalanche observations from your ventures in the backcountry HERE. You can call us at 801-524-5304 or email HERE, or include #utavy in your Instagram or Tweet us @UAClogan. To report avalanche activity in the Logan Area or to contact the local avalanche forecaster call me, Toby, at 435-757-7578. 

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.