Avalanche Advisory
Advisory: Logan Area Mountains Issued by Toby Weed for Monday - January 16, 2017 - 7:09am
bottom line

Heightened avalanche conditions exist in the backcountry, and triggered persistent slab and cornice-fall avalanches are possible. Evaluate the snow and terrain carefully. Avoid ridge-top cornices, drifted terrain, and steep rocky slopes with thin overall snow cover.




current conditions

The Tony Grove Snotel at 8400' reports 16 degrees F with 93 inches of total snow containing 168% of average SWE (Snow Water Equivalent). It's 14 degrees F at the CSI Logan Peak weather station at 9700', and 18 mph north-northwest wind. Observers report numerous natural avalanches across the zone from last week's wild storm. But everyone is also apparently finding good snow stability, with no word of triggered avalanches. Feathery surface hoar is widespread at all elevations and on slopes facing all directions.

Surface hoar is widespread in the Logan Zone

recent activity

List of notable activity from last week's natural avalanche cycle:

  • A natural avalanche hit Hwy 89 in the Beaver Canyon section of Logan Canyon just after noon Wednesday, closing the road until Thursday morning.
  • A dirt-filled natural avalanche in Zanavoo Gully in lower Logan Canyon ran about 2800' early Thursday morning, stopping 100 vertical feet above the River Trail.
  • Natural avalanche activity in the Wellsville Range was extensive, and HUGE fresh natural avalanches can be seen from across Cache Valley.
  • Observers reported large natural avalanches from the recent cycle on the east face of Mt. Magog, Cornice Ridge, Providence Peak, Hell's Kitchen, Tab Hollow, Steam Mill, Wood Camp, and Thurston Hollow in the Mount Naomi Wilderness.

Large natural avalanches from last week in the Wellsville Range above Mendon and in Wood Camp Hollow.
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

Persistent slab avalanches, failing on buried weak layers, are possible. Large natural avalanches stepping into old snow were common during last week's storm. Weak layers of faceted snow exist above and below rain-crusts at mid and lower elevations. The snow is weakest in rocky terrain where it's thin or shallow. Remotely triggered avalanches are unlikely but still possible.

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
  • Large cornices developed on the exposed ridges during the recent storm, and many are still sensitive to human weight. Cornices can break further back than expected and might trigger avalanches on drifted slopes below.
  • Fresh wind slabs may form from drifting caused by this morning's moderate north wind.
weather

High pressure aloft will settle over the Great Basin for the first half of the week. A return to an active weather pattern will occur late in the week. It'll be sunny in the mountains with a high at 8500' of 27 F, and moderate north wind becoming light from the northeast in the afternoon. It'll be mostly clear tonight, with continued light north wind and a low temperature of 16 F. Same tomorrow, with a daytime high temperature of 33 F. The next round of Pacific storminess will affect the zone starting Wednesday night, lasting into the weekend.
general announcements

Any time is a great time to practice companion rescue techniques with your partners. Companion Rescue Practice Video

The National Avalanche Center just released their Avalanche Problems Explained video... Not all avalanches are made the same. As a result, travel and decisions in avalanche terrain are influenced by the kind of avalanche you expect to encounter. Watch HERE

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.

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.