Avalanche Advisory
Advisory: Moab Area Mountains Issued by Eric Trenbeath for Monday - January 25, 2016 - 5:56am
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Today the avalanche danger is MODERATE​ on all aspects steeper than 35 degrees in upper elevation, wind exposed terrain where you can detect recent deposits of wind drifted snow. Look for tell tale signs such as smooth rounded drifts, and cracking in the snow surface, and be wary of the lee sides of gully walls, subridges, and other terrain features.

There also remains an isolated, or MODERATE avalanche danger on steep northerly facing aspects where it may be possible to trigger a lingering, persistent slab avalanche. Careful slope and snowpack analysis is recommended before venturing into this kind of terrain.




current conditions

It looks like about 5" of new snow fell between noon and midnight yesterday. Winds have not been as strong as forecasted averaging 15-25 mph with occasional gusts near 30, first from the SW and then shifting to NW by afternoon. They are currently averaging 20 mph from the NW on Pre Laurel Peak, and it is a frigid 3 degrees up there. It's currently 13 degrees at the Geyser Pass trailhead.

Thanks to Travis Nauman for this observation.

Base depth in gold Basin: 65"

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

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recent activity

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

Though winds didn't get up into the strong range, they definitely blew enough to move the new loose snow around. With the shifting wind direction, expect to find recently deposited, shallow wind slabs on the lee sides of ridge crests and terrain features on all aspects above tree line. Cross loading will also be a factor so be wary of the lee sides of gully walls and sub ridges. Look for telltale signs such as smooth rounded pillows or cracking in the snow surface.

On steep, northerly facing aspects, it may be possible to have a triggered wind slab step down to a buried weaker causing a deeper and more dangerous persistent slab avalanche.

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

We've crept back into the woods as far as persistent slab problems go and the snowpack is becoming a bit complex. Over the past week, new snow and occasional wind slabs have formed over weak, near surface facets. Several inches of graupel have stacked on top of that followed by another round of wind slab development. Additionally, slopes that avalanched over Christmas, have now filled in just enough to become repeat offenders due to the presence of weak, faceted snow on the old bed surface.

The only way to really know what's going on under the surface is to dig in and have a look. And this is the only prudent approach when considering getting on slopes steeper than about 35 degrees, particularly those with a NW-N-E aspect.


In areas where the snowpack is deep, most of our problems are confined to the upper levels. The snow shown here goes down for another 30" or so. We found the weak faceted layer to be fairly reactive, and in areas where a greater load, or more cohesive slab is overlying it, it would be possible to trigger an avalanche. Additionally, loose graupel near the surface can be a weak layer, though usually for a shorter period of time. Here it has pooled up under a rock band and is several inches thick. If you manage to find a thicker slab overriding it than the one pictured, you could find yourself going for a ride, and possibly then stepping down to the weak faceted layer below.

The CT12 Q2 sheer translates to a moderately easy sheer, meaning that it would be moderately easy to trigger an avalanche.

weather

A weak, secondary wave on a northwest flow will move through the area late morning bringing unstable air and a slight chance for snow. Otherwise look for partly sunny skies and cold temperatures. High pressure builds through the rest of the week.

Monday

A 40 percent chance of snow, mainly before 11am. Partly sunny, with a high near 14. North wind 10 to 15 mph.

Monday Night

Partly cloudy, with a low around 6. Wind chill values as low as -10. North wind 10 to 15 mph.

Tuesday

Sunny, with a high near 17. Wind chill values as low as -10. North wind around 10 mph, with gusts as high as 20 mph.

Tuesday Night

Mostly clear, with a low around 9. North northeast wind 10 to 15 mph becoming south southeast after midnight.

Wednesday

Sunny, with a high near 25.

Wednesday Night

Mostly clear, with a low around 13.

Thursday

Sunny, with a high near 27.

Thursday Night

Mostly clear, with a low around 18.

Friday

Mostly sunny, with a high near 30.

general announcements

Road Conditions: Expect to find a few inches of new snow on the road this morning. 

Thanks for sending in your observations. You can view Moab observations here. To post an observation go here.

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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.