Avalanche Advisory
Advisory: Logan Area Mountains Issued by Toby Weed for Tuesday - February 16, 2016 - 7:08am
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CONSIDERABLE (level 3): People should stay off and out from under steep slopes with soft saturated snow, and avoid drifted slopes at upper elevations. ​ Dangerous avalanche conditions exist and will develop in the backcountry today on rain saturated slopes at lower and mid elevations in the heat of the day, and in some drifted upper elevation terrain. Human-triggered avalanches are likely and natural avalanches are possible on slopes steeper than about 30 degrees. Careful snowpack evaluation, cautious route finding, and conservative decision-making will be essential again today.




special announcement

We are offering an Avalanche Awareness for Snowmobilers Course on February 25 & 27. For more information and to register go..... HERE

current conditions

The 8400' Tony Grove Snotel reported about 8 inches of wet snow from Sunday/Monday containing 1.8 inches of water. Yesterday afternoon there was 75 inches of total snow at the site, containing 105% of average water content for the date. I'm reading 26 degrees at the 9700' CSI Logan Peak weather station, and the wind sensor is rimed. Ogden Peak shows sustained and gusty westerly winds all day yesterday, diminishing a bit overnight and currently averaging in the mid twenties. Temperatures look to have stayed above freezing at lower elevations and cloud cover likely helped reduce overnight radiation heat loss. The snow at mid and lower elevations yesterday was soft, inverted, and saturated by rain, and lacking a good overnight freeze dangerous wet avalanche conditions probably still exist.


A large natural wet avalanche ran into lower elevations, but stopped above the River Trail yesterday in Lower Logan Canyon just up canyon from 2nd Dam.

recent activity
  • A wet avalanche crossed Hwy 89 in Logan Canyon at the Dugway at around 2:30 yesterday afternoon... The highway was fairly quickly cleared by a UDOT crew in the area. Remember that you don't want to try to hand dig a route around avalanches on the road because you expose yourself to following or adjacent avalanches which are likely in many areas..
  • Large natural wet avalanches occurred overnight and during the day Monday in Logan Canyon and at lower and mid elevations across the zone.
  • There were numerous natural loose wet avalanches in the heat of the day on slopes facing the south half of the compass in the Logan Zone last week.
    ***To view our updated list of backcountry observations and avalanche activity from around Utah, go to our observations page

Avalanche Problem 1
type aspect/elevation characteristics
LIKELIHOOD
LIKELY
UNLIKELY
SIZE
LARGE
SMALL
TREND
INCREASING DANGER
SAME
DECREASING DANGER
over the next 10 hours
description

Rain saturated the low elevation snow, significant natural wet avalanches occurred overnight yesterday and continued during the day with periods of solar warming on steep low and mid elevation slopes. Significant loose wet avalanches involving saturated soft snow are again likely with midday heating today on steep slopes below the rain/snow line... Dangerous wet slab avalanches remain possible in some low elevation areas with saturated snow and poor snow structure.

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 wind slab avalanches up to around 2 feet deep are possible at upper elevations today due to significant drifting from strong and sustained west winds during periods of snowfall during the Sunday/Monday storm. A thick rime or rain crust formed up to upper elevations in many areas and may be welding most of the wind slabs in place, but this lack of sensitivity may also allow people to get well out on the wind slabs before they fail.

  • Sizable wind slabs were deposited on the lee sides of ridges, cross-loaded along sub-ridges, and they formed in and around terrain features like rock outcroppings, gullies, scoops, trees, and saddles.
  • Beware the growing ridge-top cornices, which could break further back than you expect and could trigger wind slab avalanches on drifted slopes below.
  • Wind slabs may fail on weak small grained sugary snow that was on the surface last week called near surface facets, or on feathery frost crystals called surface hoar, which formed during last week's high pressure and may have been buried intact on some slopes.
  • ***Persistent and/or deep slab avalanches are still possible on drifted slopes in outlying areas with shallow weak snow.


weather

We'll see lots of sunshine today, sustained west winds, and a high temperature at 8500' of around 40 degrees. It'll be partly cloudy tonight with temperatures hovering around freezing and lighter southwest winds. We'll see increasing clouds tomorrow ahead of the next storm system and high temperatures in the mountains pushing 50 degrees! Snow is likely Wednesday night and Thursday, with 4 to 7 inches of accumulation forecast.

general announcements

Please submit snow and avalanche observations from your ventures in the backcountry HERE. You can call us at 801-524-5304 or email HERE, or include #utavy in your Instagram or Tweet us @UAClogan. To report avalanche activity in the Logan Area or to contact the local avalanche forecaster call me, Toby, at 435-757-7578. 

We'll update this advisory throughout the season on Monday, Wednesday, Friday, and Saturday mornings by about 7:30

This advisory is produced by the U.S.D.A. Forest Service, which is solely responsible for its content. It describes only general avalanche conditions and local variations always exist.