Avalanche Advisory
Advisory: Moab Area Mountains Issued by Eric Trenbeath for Tuesday - February 9, 2016 - 6:34am
bottom line

There remains what I would call an elevated MODERATE danger for triggering a persistent slab avalanche on steep, northerly facing aspects that didn't slide during the last cycle. I would continue to avoid these slopes and stick to lower angle terrain in shady locations.

There is also a MODERATE danger for triggering an isolated wind slab on slopes steeper than 35 degrees in upper elevation, wind exposed terrain.

And finally, with daytime heating there will be a MODERATE danger for wet slide activity on sun exposed slopes in the afternoon.




special announcement

Thanks to Bruce Tremper for covering for me while I was away. He set the bar pretty high and I would have expected nothing less.

This advisory is based on field work performed on Monday, February 8. With high pressure forecasted for the rest of the week, I don't foresee much of a change in avalanche conditions. Use the weather links under current conditions to stay abreast of current wind and temperature. Look for the next update on Saturday, February 13.

I will be holding a Know Before You Go avalanche awareness talk on Thursday, February 11 in Monticello at the Canyon Country Discovery Center at 6:00 p.m. Call me for details: 801-647-8896
current conditions

The January thaw has arrived in February and we have a mixed bag of spring like conditions out there including wind and sun crusts, and gloppy wet snow. Northerly winds have hammered the powder on exposed slopes above treeline, but isolated areas of soft, settled or re-crystallized powder remain in sheltered locations.

With warm daytime temperatures and strong overnight freezes, I expect we will have corn like conditions developing on south through west aspects later in the week. Best strategy for now is to stay off of these slopes and allow a smooth, supportable, melt-freeze surface to form. When it does, ride it early and then get off to avoid leaving deep ruts in the snow. Then you can return day after day to enjoy the smooth, creamy surface.

Wind damaged snow exists in most exposed locations.


But you can still find some areas of soft settled, or re-crystallized powder in sheltered areas.

Winds, temperature and humidity on Pre-Laurel Peak

New snow totals, temperature and humidity in Gold Basin

Total snow depth and temperature at Geyser Pass Trailhead
recent activity

I observed these loose, wet avalanches on a steep westerly aspect in Talking Mountain Cirque. As the snow surface develops a stout crust, slides such as these will become less likely, but you should always remain aware of signs of instability such as wet sloppy snow, and pinwheels or roller balls coming down the slope.


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 storm snow of last week has largely settled into place, and the overall appearance of the wind and sun damaged surface makes for pretty benign looking avalanche conditions. However, things are still quite tricky and dangerous on steep, northerly aspects. In my travels Monday, I observed collapsing in the snowpack, and snow pits revealed a clearly defined and widespread, reactive weak layer of buried faceted snow. With these obvious red flags, I would continue to avoid slopes steeper than 35 degrees that have a NW-N-E aspect that didn't slide during the last avalanche cycle.

Snow pit reveals a clearly defined, weak, faceted layer with a reactive shear.

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

Northeasterly ridge top winds have continued to move snow around and you may also find older, stiff wind slabs on the lee sides of ridge crests and terrain features in exposed, upper elevation terrain. Cross loading is also a factor and you may find these slabs in unusual locations. They may also be disguised by etching or wind scouring. By now, they are going to be stubborn to release, but you could trigger one in steeper more radical terrain where they also have the potential to step down into a deeper, persistent weak layer. Choose terrain carefully, largely by avoiding slopes steeper than 35 degrees in upper elevation, wind exposed terrain.

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

Sun and warm temperatures have produced some loose, wet snow avalanches on sun exposed slopes. As stouter crusts from on these aspects, they will take longer to soften and will grow less likely. Nevertheless, it is important to stay alert to signs of instability such as sloppy wet snow, and roller balls or pinwheels coming down the slopes. Stay off of and out form under steep, sun exposed slopes when these signs are present.

weather

High pressure is in store for the rest of the week.

Tuesday

Sunny, with a high near 42. North northeast wind 5 to 10 mph.

Tuesday Night

Mostly clear, with a low around 24. Northeast wind around 5 mph.

Wednesday

Sunny, with a high near 43. West wind around 5 mph.

Wednesday Night

Mostly clear, with a low around 25. North northwest wind around 10 mph.

Thursday

Sunny, with a high near 41. North northwest wind around 10 mph.

Thursday Night

Mostly clear, with a low around 27.

Friday

Sunny, with a high near 43.
general announcements

Road Conditions: Thanks to the Forest Service for stepping and getting the road plowed!

Grooming: The trails were groomed Friday.

This is a single-person operation and I can't be everywhere at once.  You can contribute to your own, community avalanche forecast by letting me know what you're finding.  You can view Moab observations here. To post an observation go here.  You can also give me a call on my cell phone at 801-647-8896

To receive this advisory by email go here.

This information does not apply to developed ski areas or highways where avalanche control is normally done.  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.