Avalanche Advisory
Advisory: Logan Area Mountains Issued by Toby Weed for Thursday - February 23, 2017 - 7:12am
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Conditions are dangerous on drifted upper elevation slopes, triggered large cornice fall and hard slab avalanches are possible. Periods of heavy snow today will cause a rising danger of storm snow avalanches. Triggered avalanches may become likely, and natural activity is possible. Evaluate snow and terrain carefully, make cautious decisions, and avoid travel on or under large cornices and steep drifted slopes.
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

Don't forget your extra goggles today. It will be a snowy day in the mountains, and the avalanche danger will increase. The 8400' Tony Grove Snotel reports 15 F and 6" of snow with .8" SWE in the last 24 hrs. It's 7 F at the CSI Logan Peak weather station at 9700'. The wind sensor may be affected by icing, but showing a 3 mph southwest wind. On Ogden Peak southwest winds are blowing 22 mph, gusting to around 40 mph. The snow was like mashed potatoes even on north facing upper elevation slopes Tuesday, but super strong southwest winds still picked it up and created dangerous hard wind slab avalanche conditions on lee slopes at upper elevations. Dropping temperatures will set up the wet snow at low and mid elevations and increase stability.

recent activity
  • No avalanches were reported yesterday.
  • Drifting from very strong southwest winds Tuesday caused some natural wind slab and cornice-fall activity on exposed upper elevation slopes.
  • Monday, I intentionally triggered a 14" deep and 20' wide storm slab on a very steep test slope above the Tony Grove Campground. The soft slab avalanche failed on small facets and ran on the 2/10 rain-crust.


I intentionally triggered this storm slab Monday on a very steep test slope above the Tony Grove Campground.
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

Periods of heavy snowfall today could create dangerous avalanche conditions at upper and mid elevations. The danger of storm slab and loose avalanches involving fresh snow will rise during the day. Natural avalanches are possible during periods of particularly heavy snowfall or with an uptick in winds.

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
  • Huge, overhanging cornices exist on the high ridges and are weak due to recent warmth and wind and can break further back than expected and trigger avalanches on slopes below.
  • Triggered hard wind slab avalanches are possible at upper elevations. Tuesday's solid wind slabs will be hidden, buried under several inches of light snow that fell during calmer conditions. Wind slabs formed on the lee side of ridges and in and around terrain features like gullies, scoops, sub-ridges, and cliff-bands.

Huge cornices exist on exposed ridges at upper elevations
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

Persistent slab avalanches, around 2' deep, failing on small faceted grains and running on the 2/10 rain-crust are possible on upper and mid elevation north facing slopes.
weather

A cold upper trough over the area today will shift east on Friday. The next system will cross the area Saturday afternoon and night, with yet another cold storm on tap for the first part of next week.

Weather Forecast: Tony Grove Lake (41.897,-111.6535), Elevation: 8800'
Today: Snow showers. High near 22. West wind around 14 mph. Chance of precipitation is 80%. Total daytime snow accumulation of 5 to 9 inches possible.
Tonight: Snow showers. Low around 11. Wind chill values as low as -1. West northwest wind 8 to 14 mph. Chance of precipitation is 80%. New snow accumulation of 5 to 9 inches possible.
Friday: Snow showers likely, mainly before 11am. Mostly cloudy, with a high near 18. Wind chill values as low as -2. West wind 9 to 14 mph. Chance of precipitation is 70%. New snow accumulation of 2 to 4 inches possible.


general announcements

Any time is a great time to practice companion rescue techniques with your partners. Companion Rescue Practice Video

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.