Avalanche Advisory
Advisory: Logan Area Mountains Issued by Toby Weed for Friday - April 15, 2016 - 7:15am
bottom line

We are no longer issuing danger ratings, but we can offer backcountry travel advice. Evaluate the snow and terrain carefully, and avoid drifted upper elevation slopes and overhanging cornices. Retreat from steep terrain as the snow softens and becomes saturated in the heat of the day.
special announcement

We will update the information this advisory intermittently as conditions change for the next couple weeks. Please continue to submit backcountry observations and we will continue to publish them.
current conditions

Along with a good shot of spring snow, yesterday's storm brought welcome colder temperatures. The mercury dropped well below freezing last night for the first time in more than a week. I'm reading 18 degrees at the 9700' CSI Logan Peak station, with northwest winds, currently averaging around 5 mph. The Tony Grove Snotel at 8400' reports 24 degrees and 9 inches of new snow and around an inch of water from yesterday. There's now 78 inches of total snow containing 100% of average water for the date. Heightened avalanche conditions exist in the backcountry today, with storm snow and fresh wind slab avalanches possible in steep upper elevation terrain. Rapid solar warming with the initial clearing this weekend will create a sudden rising danger of loose wet avalanches involving the fresh snow.

recent activity
  • Yesterday in upper Little Cottonwood Canyon, a large wet slab avalanche was triggered with a small explosive. It broke on damp facets at the ground, 5.5 feet deep. It was 200 feet wide, ran 700 feet, and produced debris 15 feet deep. This avalanche occurred on a NNE aspect at 9900 feet.
  • Locally: Large natural wet avalanches occurred during the sustained warm weather this week. We observed all kinds of heat related activity in the Logan Zone, including loose wet avalanches, large cornice falls, and dangerous wet slab avalanches.

Recent wet avalanche activity in the Wellsville Range after sustained warmth and a long string of nights with above freezing temperatures. (3-12-16, N Hells Canyon from Maple Bench)


​***To view our updated list of backcountry observations and avalanche activity from around Utah, go to our observations page

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
  • Fresh wind slab, storm slab avalanches, and sluffs involving the new snow are possible in steep terrain today.
  • Loose wet avalanches involving melt-moistened fresh snow will be likely with initial clearing this weekend. Rapid solar warming could cause a sudden increase in danger, with natural wet activity becoming likely.
  • As temperatures rise in the mountains again the large cornices hanging over some slopes will be of concern. As the large overhanging cornices soften with the warmth they can also become easier to trigger and often break further back than expected. Obviously, you should avoid travel on and under large cornices in the heat of the day.

Avalanche Problem 2
type aspect/elevation characteristics
LIKELIHOOD
LIKELY
UNLIKELY
SIZE
LARGE
SMALL
TREND
INCREASING DANGER
SAME
DECREASING DANGER
over the next 12 hours
description

The large wet slab in the Wasatch yesterday indicates potential for this kind of activity around here. Colder temperatures should help matters, but they will be short lived, and you should keep the potential for dangerous wet slabs in mind as you make terrain decisions. Wet slabs are difficult to predict and difficult to trigger. They are also scary because they can be like an avalanche of concrete.
weather

Today: Snow showers. Some thunder is also possible. High near 36. North northwest wind 7 to 15 mph. Chance of precipitation is 80%. Total daytime snow accumulation of 1 to 3 inches possible.
Tonight: A 40 percent chance of snow showers before midnight. Mostly cloudy, with a low around 24. North northeast wind 17 to 21 mph. New snow accumulation of less than a half inch possible.
Saturday: Mostly sunny, with a high near 43. North northeast wind 10 to 14 mph.
Saturday Night: Partly cloudy, with a low around 25. North wind 10 to 18 mph becoming east northeast after midnight.
Sunday: Mostly sunny, with a high near 44. East northeast wind 5 to 10 mph.



general announcements

The National Avalanche Center recently completed an animated tutorial on the North American Avalanche Danger Scale.  HERE

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. 

 We'll be issuing intermittent advisories for the next couple weeks as weather dictates.....

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.