Avalanche Advisory
Advisory: Logan Area Mountains Issued by Toby Weed for Monday - February 5, 2018 - 7:22am
bottom line

Heightened avalanche conditions exist on drifted slopes where human triggered wind slab avalanches and cornice falls are possible. Dangerous persistent slab avalanches are unlikely but remain possible on isolated slopes plagued by poor snow structure.

  • Evaluate snow and terrain carefully.
  • Avoid travel on or under large ridge top cornices and steep drifted slopes.
    I will update this advisory on Wednesday, 2/7/18



special announcement

The CROWBAR backcountry ski race is this Saturday February 10 at Swan Peak/Garden City Canyon. More info and registration at http://CrowbarSkiRace.org.
current conditions

Despite nearly constant cloud cover, unwelcome warmth, inccesant west wind, and a bit of rain over the weekend continued to decimate the snowpack, burning off south facing slopes at lower and mid elevations and turning nice trails to mud and ice. The Tony Grove Snotel at 8400' reports rain yesterday and a couple inches of new snow overnight, with .6" SWE in 24 hours. It's 31°F, and there's 56 inches of total snow at the site containing 90% of normal SWE (or Snow Water Equivalent). It's 34°F at the UDOT Hwy 89 Logan Summit sheds, and a west-northwest wind is blowing 20 to 25 mph, with a 60 mph gust early this morning.

recent activity

Other than natural cornice fall and wind slab activity last week at upper elevations, no avalanches were reported recently 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

Very strong west winds overnight drifted the heavy new snow into lee slope avalanche starting zones and continued to build cornices. You could easily trigger cornice falls and wind slab avalanches around a foot deep in drifted upper elevation terrain, and natural cornice falls are possible as strong westerly winds continue today.

  • Watch for and avoid drifted snow on steep lee slopes and in and around terrain features like sub-ridges, gullies, scoops, and rock outcrops.
  • Avoid travel on or under large ridge top cornices, which might break further back than expected and could trigger wind slab avalanches on drifted slopes below.
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

Avalanches stepping into old snow remain possible on isolated steep slopes in the backcountry. Rain and warm temperatures may be causing a change in slab properties or moistening layers with weak faceted snow on some mid and lower elevation slopes. Also, fresh drifts likely formed on some lee slopes with poor snow structure, overloading weak faceted snow.

  • Widespread buried faceted layers appear dormant now, and persistent slab avalanches are becoming less and less likely to trigger with time, but if you trigger one it could be dangerous.
  • Pay attention to possible signs of instability like cracking and whumpfing or collapsing, but remember these signs aren't always present when avalanches are triggered, so you have to dig down into the snow to find poor snow structure.
  • Persistent slab avalanches are often triggered from low on the slope, and might be triggered remotely, from a distance or below.​
weather

Northwest flow will continue across the Great Basin through the week. A couple of weather disturbances embedded into this northwest flow will cross northern Utah today through Tuesday.

  • Today: Snow showers likely, mainly after 11am. Mostly cloudy, with a temperature falling to around 28 by 8am. Breezy, with a west wind 18 to 28 mph, with gusts as high as 41 mph. Chance of precipitation is 60%. Total daytime snow accumulation of 1 to 2 inches possible.
  • Tonight: Scattered snow showers. Mostly cloudy, with a low around 21. West wind 15 to 20 mph. Chance of precipitation is 50%. New snow accumulation of less than one inch possible.
  • Tuesday: Snow showers likely, mainly before 11am. Mostly cloudy, with a high near 30. West northwest wind 11 to 13 mph. Chance of precipitation is 60%. New snow accumulation of 1 to 3 inches possible.
general announcements

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

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.​

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 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.