Avalanche Advisory
Advisory: Logan Area Mountains Issued by Toby Weed for Sunday - February 19, 2017 - 6:58am
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Heightened avalanche conditions already exist at upper elevations this morning and heavy snow and wind will cause the danger to rise during the day. Dangerous conditions could develop on drifted upper elevation slopes, with triggered wind slab avalanches becoming likely. Soft slab avalanches and sluffs involving new snow are possible. Evaluate snow and terrain carefully, and avoid travel on or under 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

Expect wet and windy conditions in the mountains today, with lowering snow densities and the rain/snow line dropping down to around 6000'. The 8400' Tony Grove Snotel reports 31 F, 6" of new snow, and perhaps a bit of rain overnight. There's 104" of total snow containing 162% of average SWE (Snow Water Equivalent) . It's 25 F at the CSI Logan Peak weather station at 9700', and the wind is from the south at 22 mph, gusting to 56 mph early this morning. The new snow is helping to freshen-up and smooth-in variable and crusty backcountry snow conditions at upper elevations, but rain is accelerating melt lower down.

recent activity
  • Numerous shallow sled and board triggered wind slabs were reported from drifted upper elevation terrain in the Bear River Range last weekend and early this week. The expected and easily triggered shallow soft slab avalanches occurred on very steep slopes, and were about 8" deep. Several triggered wet and dry sluffs were also reported.
  • Warmth trapped by thin clouds affected the snow on north facing mid-elevation slopes, and my party triggered a few small wet sluffs in south Wood Camp Thursday afternoon.
  • Thursday, a party observed a huge cornice that had recently cracked deeply and collapsed on the ridge above DB Bowl in Logan Dry Canyon. There were sled tracks in the area of the fracture, but it's unknown if the collapse was triggered or if it occurred after the fact.

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
  • Triggered wind slab avalanches are possible at upper elevations, and will become likely with continued drifting from west winds today. Strong south winds overnight drifted fresh snow into terrain features and lee slope starting zones, creating shallow wind slabs. Drifts at upper elevations formed on weak faceted snow above last week's thick crust and could be pretty sensitive today. Wind slab avalanches could run fast and far on last week's rain-crust.
  • Avoid drifted snow on the lee side of ridges and in and around terrain features like gullies, scoops, sub-ridges, and cliff-bands.
  • Wind slabs made up of stiffer drifted snow often look rounded and chalky and may produce hollow, drum-like sounds.
  • Cornices are suspect due to the recent warmth and wind. Avoid travel on or below large overhanging cornices, especially in the midday heat. Cornices can break further back than expected and might trigger avalanches on 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

The danger of soft slab and loose avalanches involving storm snow will rise today as heavy snow continues to rapidly accumulate on steep slopes.

weather

An elongated upper level trough will press east across the eastern Great Basin today. High pressure aloft will develop over Utah Monday, with a mild southwest flow aloft Tuesday. A potentially strong winter storm could impact the region beginning midweek.

Today: Snow. High near 35. West wind 13 to 20 mph. Chance of precipitation is 100%. Total daytime snow accumulation of 5 to 9 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.