Avalanche Advisory
Advisory: Logan Area Mountains Issued by Toby Weed for Monday - February 20, 2017 - 6:59am
bottom line

The avalanche danger is MODERATE, but strengthening south wind is causing it to rise. Heightened conditions exist at upper and mid elevations, and even small avalanches could run fast and far on a bulletproof rain-crust. Drifting will cause dangerous conditions on exposed upper elevation slopes, with triggered wind slab avalanches becoming likely and naturals possible. Soft slab avalanches and wet sluffs involving new snow are possible. Evaluate snow and terrain carefully, avoid travel in drifted terrain and on steep slopes with fresh saturated snow.




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

Heavy, wet, maritime-like new snow is helping backcountry snow conditions at upper elevations, but rain is accelerating melt lower down. The 8400' Tony Grove Snotel reports about a foot of heavy new snow and 2" SWE (Snow Water Equivalent) in the last 48 hrs. It's 30 F and there's 107" of total snow containing 164% of average SWE. It's 24 F at the CSI Logan Peak weather station at 9700', and after slacking off a bit yesterday and overnight, a south wind is increasing again and is blowing 26 mph, gusting to 40 mph.
recent activity
  • ​Several people reported easily triggering wet sluffs involving saturated storm snow at mid elevations in the backcountry near Beaver Mountain yesterday.
  • 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 could become likely with drifting from increasing southwest winds today. Drifts at upper elevations formed on weak faceted snow above last week's thick crust, and might not be all that sensitive to triggering after a day of settlement. With continued drifting today, wind slabs will likely be stiffer, better connected, and a bit less manageable than they were yesterday.
  • 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

Triggered soft slab and loose wet avalanches involving heavy storm snow are possible at upper and mid elevations.

  • Storm slab avalanches may fail on a density change within the new snow or on faceted snow above the solid and slick 2/10 rain-crust.
  • Predictable wet sluffs entraining significant piles of saturated surface snow are possible on steep mid elevation slopes facing any direction, most likely to occur during midday warmth.
weather

A mild southwest flow will develop over Utah today and continue through Tuesday. A cold front Tuesday night will usher in a period of cold unsettled weather through the end of the week. Snow showers are likely today, with 2 to 4 inches possible, 8500' high temperature of 37 F, and southwest winds 15 to 25 mph, gusting to 40 mph. 2 to 4 inches of snow is possible tonight, southwest winds 22 to 31 mph, gusting to 45 mph, and temperatures will rise to about 42 F. Snow is likely tomorrow, with 2 to 4 inches possible, temperature falling to 36 F by 5:00 PM, southwest wind 25 to 30 mph and gusts to 46 mph. 4 to 8 inches of snow on Tuesday night with a low of 22 F.
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.