Avalanche Advisory
Advisory: Logan Area Mountains Issued by Toby Weed for Wednesday - February 17, 2016 - 7:14am
bottom line

CONSIDERABLE (level 3): People should continue to stay off of and out from under steep slopes with soft saturated snow. 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. You could trigger wind slab avalanches on drifted upper elevation slopes 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 reports 32 degrees this morning and there's 73 inches of total snow containing 103% of average water content for the date. I'm reading 34 degrees at the 9700' CSI Logan Peak weather station, and south winds averaging 25 mph this morning. The snow at mid and lower elevations yesterday was very soft, inverted, and saturated by rain, and lacking a good overnight freeze again and with very warm temperatures forecast for today, dangerous wet avalanche conditions will again exist at lower elevations.

A couple natural loose wet avalanches hit Hwy 89 in the Dugway on Monday. The second one crossed both lanes at around 2:30 in the afternoon. (A.Ward 2-15-16)

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

Expect a rising danger of wet avalanches at low elevations as temperatures soar in the Mountains today. Rain saturated the low elevation snow, significant natural wet avalanches occurred Monday 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 again possible at upper elevations today. 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.

  • Increasing south wind today will create fresh drifts in lee slope depostion areas.
  • Sizable wind slabs were deposited Sunday 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 and overhanging 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 increasing clouds and south wind ahead of the next storm system. and high temperatures in the mountains pushing 50 degrees! Expect increasing south winds, averaging in the mid twenties and gusting to around 40 mph. Snow is likely tonight and Thursday, with 4 to 9 inches of accumulation forecast. Expect very windy conditions in the mountains, periods of heavy snow, thunder and lightning possible, and dropping temperatures with the storm tomorrow.
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.