Avalanche Advisory
Advisory: Logan Area Mountains Issued by Toby Weed for Friday - March 17, 2017 - 6:16am
bottom line

Warmth and sun will create heightened wet avalanche conditions in the backcountry. Loose wet, large cornice-fall, deep slab, wet slab, and glide avalanches are all possible and most likely during the heat of the day. Natural avalanches are possible. Evaluate snow and terrain carefully. Stay off of and out from under large cornices, glide cracks, and steep slopes with warmth-softened saturated snow.




special announcement

Discount lift tickets for Beaver Mountain, Snowbasin, Powder Mountain, and the Central Wasatch resorts are donated by the resorts to benefit the Utah Avalanche Center. Details and order information here.

current conditions

Once again, temperatures stayed well above freezing last night across the zone, but clear skies allowed a superficial surface refreeze. The Tony Grove Snotel ​at 8400' reports 37 °F and 108" of total snow, with 159% of average SWE (Snow Water Equivalent)​. It's 33 °F and a 16 mph southwest wind at the 9700' CSI Logan Peak weather station. Rising temperatures and sun will quickly soften the snow surface, and heightened wet avalanche conditions will develop early again in sunny terrain.


You know, when alone in the wilderness and you feel like you're being watched! Although there's not many people out in the backcountry these days, be advised, there is a lot of wildlife near the rapidly retreating snow line.
recent activity

A large deep slab avalanche was observed Saturday near White Pine Lake. The scary 4-foot deep and 175' wide avalanche occurred Friday night or Saturday morning and was probably triggered by natural cornice fall from the cliffs above, but there were snowbike and sled tracks in the area. See report here

In the past several days, there was a good deal of natural cornice fall and loose wet avalanche activity in the Logan Zone.
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
  • Warm temperatures and sun create heightened wet avalanche conditions earlier today. Surface snow will soften on steep slopes. Triggered loose wet avalanches are possible during the heat of the day.
  • Watch for signs of wet instability like roller balls, pin-wheels and natural sluffs under trees or rock outcroppings.
  • Avoid being on or under steep slopes during warm weather if wet snow is unsupportable.
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

Deep slab avalanches are possible as previously drifted upper and mid elevation slopes are warmed and existing hard slabs soften in the heat. A couple of isolated hard slab avalanches failing on weak surface snow and running on a rock-hard rain-crust formed in mid-February have occurred in the last couple weeks on upper elevation east facing slopes.

Isolated hard slab avalanches failing on weak snow above solid 2/10 rain-crust, 3/11 White Pine Lake and 3/3 Hidden Lake, both on east facing slopes above 8500'. Runnels formed by February rain are visible in the bed surfaces...

Glide and wet slab avalanches avalanches are possible in steep terrain and can occur anytime of day during this unseasonably warm weather.

Avoid being under glide cracks like these on the slabs near Rodeo Ridge above the Ogden Valley. In warm weather, you never know when a glide avalanche might occur.
Avalanche Problem 3
type aspect/elevation characteristics
LIKELIHOOD
LIKELY
UNLIKELY
SIZE
LARGE
SMALL
TREND
INCREASING DANGER
SAME
DECREASING DANGER
over the next 24 hours
description
  • Warm temperatures will cause cornices to buckle and calve naturally. Large cornice falls are most likely during the heat of the day, but possible anytime.
  • Huge, overhanging cornices can break further back than expected and trigger avalanches on slopes below.

Overhanging cornices the size of enclosed snowmobile trailers are collapsing due to heat and causing wet avalanches.

Here's scary video from 2011 on Cornice Ridge. Watch as a rider breaks a cornice and takes an unexpected ride down the hill.

Tanner Gittins, 2/13/2011
weather

High pressure over the region today will give way to a very mild southwest flow on Saturday. A more active pattern is expected to develop for the first part of next week. Today will be mostly sunny, a high temperature at 8500' of 52 °F, and 7 to 13 mph south-southwest wind. Tonight will be partly cloudy, a low temperature of 39 °F and 9 to 16 mph south-southwest wind. Tomorrow will be mostly sunny, with a high of 56 °F and 16 to 20 mph south-southwest wind.
general announcements

Do you buy groceries at Smiths? When you register your Smith’s rewards card with their Community Rewards program, they will donate to the Utah Avalanche Center whenever you make a purchase. It's easy, only takes a minute, and doesn't cost you anything. Details here.

If you sign up for AmazonSmile and designate the Utah Avalanche Center as your favorite charity, they will donate a portion of everything you spend to the UAC. It doesn't cost you a penny and we'd really appreciate the help.

Your information can save lives. If you see anything we should know please help us out by submitting snow and avalanche observations. You can call us at 801-524-5304, email by clicking HERE, or include @utavy in your Instagram. In the Logan Area you can reach me at 435-757-7578

We will update this advisory regularly on Monday, Wednesday, Friday, and Saturday mornings by about 7:30.

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