Avalanche Advisory
Advisory: Logan Area Mountains Issued by Toby Weed for Friday - March 18, 2016 - 6:45am
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MODERATE (level 2): Heightened wind slab and cornice fall conditions exist and triggered avalanches are possible in steep drifted terrain. The danger of sizable loose wet avalanches entraining new snow will rise rapidly on sunny slopes as the fresh snow is initially warmed and becomes moist and sticky. Evaluate the snow and terrain carefully, and stay off and out from under steep sunny slopes in the heat of the day.
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current conditions

The Bear River Range picked up a few feet of fresh powder this week, and we've found very nice deep powder riding conditions. Cloud cover and cool mountain temperatures have so far kept the snow nice and dry, but it looks like the powerful March sun will be out today. Air temperatures should stay below freezing, but the fresh snow on sunny slopes will probably become damp, sticky, and prone to sluffing as it is initially (rapidly) warmed. The Tony Grove Snotel at 8400' reports 17 degrees ​this morning and an even 100 inches of total snow containing 107% of average water for the date. I'm reading 11 degrees at the 9700' CSI Logan Peak weather station, but the wind sensor is still rimed. Mt Ogden shows northwest winds averaging 10 to 15 mph.


Cornices grew significantly this week with all the new snow and sustained westerly winds. These can fool people by breaking further back than expected, and might trigger avalanches on slopes below. Natural cornice falls are likely with the significant warm-up expected in the mountains this weekend.
recent activity
  • Riders tested numerous steep slopes in the Central Bear River Range yesterday, but not all without incident. The fourth rider to cross a steep drifted mid elevation northeast facing slope in the Franklin Basin Area triggered a 3-foot deep by around 80' wide avalanche. He was caught and carried a short distance and partially buried, but thankfully not injured.
  • I was able to trigger a small wind slab on a very steep test slope in the Hell's Kitchen area yesterday. The slab was only about 15' wide and 14" deep, releasing on melt-freeze snow from last week. The snow appeared fairly stable otherwise, and we did not see any evidence of recent natural activity.


The fourth rider crossing a slope triggered and was caught, carried, and partially buried by a wind slab avalanche in the Franklin Basin Area yesterday, (3-17-2016)

***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 24 hours
description

Sustained westerly wind, sometimes during periods of heavy snowfall in the past several days created areas with heightened wind slab and cornice fall conditions exist in drifted terrain.

  • Avoid recent drifts and stiffer wind slabs on the lee sides of ridges, cross-loaded along sub-ridges, and in and around terrain features like rock outcroppings, gullies, scoops, trees, and saddles. Cracking is a sign of potential instability.
  • Beware large overhanging ridge-top cornices, which could break further back than you expect and might trigger avalanches on drifted slopes below. Natural cornice falls are possible, and may become likely when the sun comes out and mountain temperatures warm up.

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

The powerful March sun will be out in force in the mountains today for the first time all week. Solar warming will moisten the fresh snow causing it to become sticky. Loose wet avalanches entraining the copious fresh snow are possible and may become likely on sunny slopes, and debris piles could be fairly large especially on sustained steep slopes. Heat related slab avalanches involving the new snow are possible in some steep sunny areas. The danger of wet avalanches is likely to rise and become more widespread with increasing mountain temperatures over the weekend.

weather

A RIDGE OF HIGH PRESSURE WILL BUILD IN OVER THE REGION TODAY THROUGH THE WEEKEND WITH A WARMING TREND BEGINNING SATURDAY. UNSETTLED AND COOLER WEATHER IS EXPECTED FOR THE MIDDLE OF NEXT WEEK.
Today: Mostly sunny, with a high near 27. North northeast wind 5 to 14 mph becoming west northwest in the afternoon.
Tonight: Mostly clear, with a low around 17. West northwest wind 7 to 13 mph becoming north northeast after midnight.
Saturday: Sunny, with a high near 36. North northeast wind 5 to 7 mph becoming west southwest in the afternoon.

general announcements

The National Avalanche Center recently completed an animated tutorial on the North American Avalanche Danger Scale. 

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 avalance 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.