Avalanche Advisory
Advisory: Logan Area Mountains Issued by Toby Weed for Friday - February 16, 2018 - 6:40am
bottom line

Heightened avalanche conditions exist in the backcountry, and the danger is MODERATE. Human triggered wind slab and storm snow avalanches are possible. Drifting from increasing southwest winds this afternoon will cause a rising danger, and dangerous conditions may develop in exposed upper elevation terrain, with natural avalanches possible and human triggered avalanches likely.

  • Triggered wind slab avalanches 1 to 2 feet deep are possible.
  • Evaluate snow and terrain carefully.




special announcement

Episode 5 of the UAC podcast To Hell in a Heartbeat - A Conversation With Tom Diegel and Matt Clevenger About the 12.26.08 Full Burial on Little Water is live. This podcast talks with Matt and Tom about their experience and the massive success of the To Hell in a Heartbeat video which has been viewed almost 3M times. Check it out on ITunes, Stitcher, the UAC blog, or wherever you get your podcasts.

current conditions

We found fine Utah powder conditions yesterday in the Central Bear River Range, with well over a foot of nice new snow at upper elevations and several much needed inches down lower and at the trail-heads, refreshing access routes. Human triggered wind slab and storm snow avalanches are possible on many steep upper and mid-elevation slopes.

  • The Tony Grove Snotel at 8400' reports about 14" of new snow and 1.0" SWE (or Snow Water Equivalent) from yesterday's storm. It's 11°F, and there's 65 inches of total snow, with 84% of normal SWE.
  • I'm reading 10°F at the UDOT Hwy 89 Logan Summit sheds, and a northwest wind is blowing 5 to 10 mph.
recent activity
  • We noticed a couple natural avalanches near Mt. Magog that occurred during periods of heavy snow and strong wind yesterday. These soft wind slab avalanches, 1' deep and about 50' wide, were on drifted east facing slopes above around 9200' in elevation, and were likely triggered by cornice falls.
  • Snowboarders unintentionally triggered, but were able to escape a couple soft storm slab avalanches in Miller Bowl above Tony Grove Lake yesterday. The 10" deep avalanches on a very steep NNE facing slope at around 8700' failed within the new snow and ran on a widespread slick rain-crust.

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

Southwest winds will increase significantly by this afternoon and will find plenty of nice light snow to drift. The increasing wind will build up existing slabs and create new drifts in lee slope deposition areas at upper elevations. Today's wind slabs in exposed terrain could be stiffer, thicker, wider, run farther, and be less manageable than they were yesterday.

  • Wind slabs are made up of stiffer, drifted snow. They can appear chalky and rounded and can make hollow drum-like sounds.
  • Cracking in the snow is a red flag.
  • Wind slab avalanches are possible on corniced slopes, and freshly built cornices often break further back than expected.
  • Avoid drifted snow in and around terrain features like sub-ridges, cliff bands, scoops, and gullies.
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

Soft storm slab and loose avalanches entraining yesterday's new snow and running on a slick ice-crust are possible in steep terrain at upper and mid-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

Continue to practice safe travel protocols by exposing only one person at a time when moving through avalanche terrain. Widespread buried faceted layers appear dormant for now, but if you trigger an avalanche running on old snow it could be dangerous. Continue to avoid very steep rocky slopes with shallow snow and poor snow structure.

weather

A weak system will impact far northern Utah and southwest Wyoming today and tomorrow. A colder and wetter storm system is expected to significantly impact the entire region this weekend into early next week.

  • Today: A 30 percent chance of snow after 11am. Mostly cloudy, with a high near 23. Wind chill values as low as -10. Windy, with a southwest wind 21 to 26 mph increasing to 27 to 32 mph in the afternoon. Winds could gust as high as 46 mph. Total daytime snow accumulation of less than a half inch possible.
  • Tonight: A 30 percent chance of snow, mainly before 11pm. Mostly cloudy, with a temperature rising to around 20 by 2am. Wind chill values as low as -5. Windy, with a west wind 32 to 38 mph, with gusts as high as 55 mph. New snow accumulation of 1 to 3 inches possible.
  • Saturday: A 30 percent chance of snow. Mostly cloudy, with a high near 31. Wind chill values as low as zero. Windy, with a west southwest wind 32 to 41 mph, with gusts as high as 60 mph. New snow accumulation of less than one inch possible.
general announcements

The latest UAC podcast - "Recreating Like a Pro - A Conversation with IFMGA guide Anna Keeling" is live. This podcast will be ideal for anyone looking to pick up some tips and tricks from a professional mountain guide for recreating in the winter backcountry environment.‚Äč

We have discount lift tickets for Alta, Snowbird, Brighton, Solitude, Snowbasin,and Beaver Mountain. Details and order information here. All proceeds from your purchase go towards paying for avalanche forecasting and education.

The UAC Marketplace is online. The holiday auction is closed, but our online marketplace still has deals on skis, packs, airbag packs, beacons, snowshoes, soft goods and much more.

The UAC has new support programs with Outdoor Research and Darn Tough. Support the UAC through your daily shopping. When you shop at Smith's, or online at Outdoor Research, REI, Backcountry.com, Darn Tough, Patagonia, NRS, Amazon, eBay a portion of your purchase will be donated to the FUAC. See our Donate Page for more details on how you can support the UAC when you shop.

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 Check it out on ITunes, Stitcher, the UAC blog, or wherever you get your podcasts.

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

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

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 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.