Avalanche Advisory
Advisory: Logan Area Mountains Issued by Toby Weed for Sunday - December 25, 2016 - 7:04am
bottom line

A Christmas blizzard is creating dangerous avalanche conditions in the backcountry, and you should avoid travel in avalanche terrain.

  • Stay off of and out from under slopes steeper than 30 degrees, and avoid avalanche runout zones.
  • Natural avalanches are possible, especially during periods of particularly heavy snowfall or strong wind.
special announcement

***Discount lift tickets for Beaver Mountain, Snowbasin, Powder Mountain, and the Central Wasatch resorts are now available, donated by the resorts to benefit the Utah Avalanche Center. Details and order information here. These make a great holiday gift and all proceeds go towards paying for avalanche forecasting and education!
current conditions

The Tony Grove Snotel at 8400' reports 15 degrees this morning and there's about 7" of new snow. There's 50" of total snow at the site, now containing 115% of average water content for the date. It's a chilly 4 degrees at the CSI Logan Peak weather station at 9700'. The strong southeast winds from yesterday calmed overnight, with average wind speeds in the single digits for several hours. The wind veered from the northwest early this morning and is intensifying, currently averaging around 25 mph, with gusts to 35 mph.

Feathery surface hoar or frost crystals on the snow surface yesterday in the Franklin Basin Area are now buried under a bit of new snow from overnight... These glittery crystals may be the failing layer for this weekend's storm snow avalanches on some slopes, or they could become a tricky buried persistent weak layer for triggered avalanches next week. (12-23-16)
recent activity

A natural avalanche cycle occurred across the zone last Friday during the storm and included sizable activity on south and east facing slopes. No significant avalanches were reported locally since then.
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

The danger of storm slab avalanches will continue to rise during the day as new snow stacks up on weak surface snow.

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

Drifting from sustained and rather uncommon east-southeast winds Friday night and yesterday formed sensitive wind slabs in unexpected places. Yesterday's drifts are now hidden, buried by several inches of new snow. The danger of wind slab avalanches will continue to rise with drifting from intensifying and gusty west-northwest winds.

  • Fresh wind slabs appear rounded and chalky and can produce hollow, drum-like sounds.
  • Avoid drifted snow on the lee side of major ridges and in and around terrain features like gullies, scoops, sub-ridges, and cliff-bands.
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
  • Mid-pack weak layers of buried graupel and small-grained near surface facets exist, and you might trigger an avalanche stepping into old snow in some areas.
  • Dangerous deep slab avalanches, failing on weak faceted snow or depth hoar near the ground are possible, especially on upper elevation north facing slopes.
  • Additional overloading and drifting snow will cause a rising danger of persistent and deep slab avalanches on some slopes.
weather

The National Weather Service has continued a Winter Storm Warning for most of Utah and southern Idaho through tomorrow morning. Expect blizzard conditions in the mountains today with dropping temperatures, heavy snowfall, and intensifying west-northwest winds. Temperatures should drop to around 10 degrees, winds could gust into the 50 mph range, and 4 to 8 additional inches of snow forecast by this evening. Snowfall should taper off overnight, and northwest winds will gradually diminish.
general announcements

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

Check out Avalanche Canada's "Rescue at Cherry Bowl" story HERE

Between now and Jan 15th: Donate to the Utah Avalanche Center by shopping at Whole Foods Market Utah! When you visit any Utah Whole Foods Market locations, bring your re-usable bags, Whole Foods will donate a dime per bag to the Utah Avalanche Center - if you say DONATE my bag credit.

We will update this advisory regularly on Monday, Wednesday, Friday, and Saturday mornings by about 7:30...

Remember your information can save lives. If you see anything we should know 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. In the Logan Area you can get ahold of me at 435-757-7578

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.