UDOT PLANNED AVALANCHE CLOSURES!!

Forecast for the Logan Area Mountains

Toby Weed
Issued by Toby Weed for
Thursday, December 28, 2017

Dangerous avalanche conditions exist and human triggered avalanches are likely on many slopes in the backcountry..

  • You could trigger avalanches from a distance or from below.
  • Evaluate snow and terrain carefully, make conservative decisions.
  • Continue to avoid travel in avalanche terrain. Play in the flat meadows and on low angled slopes, well away from the steep hills.
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Moderate
Considerable
High
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Learn how to read the forecast here
Weather and Snow

Lots of heavy snow and drifting from strong west winds overloaded widespread weak sugary snow, and dangerous avalanche conditions exist in the backcountry. The Tony Grove Snotel at 8400' reports 26°F and 45 inches of total snow containing 107% of normal SWE (Snow Water Equivalent). The site recorded around 25" with 3.9" SWE between Friday, 12/22/17 and Christmas Night. It's 19°F at the 9700' CSI Logan Peak weather station, and the wind sensor is still not reading due to ice. Average windspeeds calmed into the single digits at the UDOT Hwy 89 summit weather station with west wind gusting to around 15 mph.

  • Shallow early season snow conditions exist, and fresh powder is now hiding some big rocks. I've seen several badly damaged sleds in the past couple days. Travel cautiously and keep your speed down.

Recent Avalanches
  • Yesterday a rider reported triggering another good sized persistent slab avalanche in the Providence Canyon Area

On 12/26/17,

  • A 20-year-old rider was rescued by his party after being caught, carried, mostly buried, and pinned against a tree in Boss Canyon near the Idaho State Line in the Franklin Basin Area.
  • Several riders were caught and carried and partially buried in an avalanche on Whiskey Hill in the Monte Cristo Area in upper Ogden Canyon.
  • Riders remote triggered a good sized avalanche in the Rodeo Grounds on the east side of Logan Peak.
  • A very large avalanche was remote triggered yesterday in the Western Uintas.

Numerous natural avalanches were reported locally since 12/23/17; including in the Tony Grove Lake Area, Bunch Grass, the Wellsville Mountain Wilderness, Egan Basin and in the Cub River Area in southeast Idaho.

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Avalanche Problem #1
Wind Drifted Snow
Type
Location
Likelihood
Size
Description

Across the Logan Zone, wind slabs formed on weak preexisting snow. Dangerous wind slab avalanche conditions exist in exposed terrain at upper elevations, with natural activity and large avalanches possible. Human triggered avalanches are possible on drifted slopes at all elevations.

  • Wind slabs are now pretty hard in many areas, and these have a nasty tendency to allow people to get out on them before releasing.
  • You could trigger large wind slab avalanches from a distance or below.
  • Wind slabs, consisting of stiffer, drifted snow may be chalky in appearance and might produce hollow sounds.
  • Avoid drifted snow in steep terrain near ridges and in and around terrain features like gullies, saddles, rock bands, scoops, and sub-ridges.
Avalanche Problem #2
Persistent Weak Layer
Type
Location
Likelihood
Size
Description

Along with the gift of powder snow, Santa also brought a slab made up of stronger snow that now sits precariously upon widespread weak sugary snow formed during the prolonged December high pressure system. Persistent slab avalanches are likely even in sheltered areas.

  • Pay attention to possible signs of instability like cracking and whumpfing or collapsing.
  • Avalanches might be triggered remotely, from a distance, or worse, from below.
  • A ride in even a small avalanche could be particularly dangerous now due to hard underlying snow and real potential for being dragged through rocks or deadfall below.

Cracking like this and collapsing are sure signs of persistent instability.

Additional Information

High pressure aloft along the west coast will maintain a generally dry and mild westerly flow aloft across much of Utah heading into the weekend. A fast-moving weather disturbance will cross northern Utah Saturday.

  • It'll be partly sunny today with a high temperature at 8500' around 32°F and 17 to 22 mph west wind.
  • There's a chance of a trace of snow late tonight. It'll be mostly cloudy with a low near 25°F and 22 mph west wind.
  • A half inch of snow is possible Friday morning. Expect partly sunny conditions with a high temperature around 38°F and 18 to 21 mph west wind.
General Announcements

We're excited to introduce for the 2017/2018 winter the Utah Avalanche Center podcast, hosted by forecaster Drew Hardesty and produced by KUER's Benjamin Bombard. The podcast will include engaging stories, interviews, and lessons learned - all things avalanche to help keep people on top of the snow instead of buried beneath it - and easily found on ITunes, Stitcher, the UAC blog, or wherever you get your podcasts.

Discount lift tickets for Alta, Snowbird, Brighton, Solitude, Deer Valley, Snowbasin, and Beaver Mountain are now available, donated by the resorts to benefit the Utah Avalanche Center. Details and order information here. All proceeds go towards paying for avalanche forecasting and education!

Now is a great time to practice companion rescue techniques with your backcountry partners. Here's our rescue practice video.

Go HERE for a list of UAC classes.

EMAIL ADVISORY: If you would like to get the daily advisory by email you will need to subscribe here.

Benefit the Utah Avalanche Center when you shop from Backcountry.com or REI: Click this link for Backcountry.com or this link to REI, shop, and they will donate a percent of your purchase price to the UAC. Both offer free shipping (with some conditions) so this costs you nothing!

Benefit the Utah Avalanche Center when you buy or sell on ebay - set the Utah Avalanche Center as a favorite non-profit in your ebay account here and click on ebay gives when you buy or sell. You can choose to have your seller fees donated to the UAC, which doesn't cost you a penny.

Remember your information can save lives. If you see anything we should know about, please help us out by submitting snow and avalanche observations. You can also call us at 801-524-5304, email by clicking HERE, or include #utavy in your tweet or Instagram.

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 occur.