Avalanche Advisory
Advisory: Moab Area Mountains Issued by Eric Trenbeath for Friday - February 14, 2014 - 6:51am
bottom line

The avalanche danger is CONSIDERABLE on slopes steeper than 35 degrees that have recent deposits of wind drifted snow. This danger is primarily located on, but not limited to, mid to upper elevation slopes with N-E-SE aspects. Considerable danger means that natural avalanches are possible and human triggered avalanches are likely. There is also a CONSIDERABLE danger for triggering a buried persistent slab. Back country travelers will need to practice safe travel techniques, staying off of, and out from under steep terrain. With warming temperatures this weekend, there is also a MODERATE danger for wet slide activity, primarily on southerly aspects. At lower elevations however, this danger will be possible on all aspects.
special avalanche bulletin

Though things aren't coming apart at the seams like they are in the rest of the state, dangerous avalanche conditions still exist in the mountains of SE Utah. No new snow has fallen since Monday, February 10th, but sustained westerly winds through the week have continued to move snow around causing deep drifts on leeward slopes, primarily at upper elevations. The additional load is adding a lot of stress to the underlying, weak snow pack, and numerous natural avalanches ran last weekend. Slopes that haven't run are hanging in a tenuous balance, further stressed by continued wind loading. Back country travelers need to travel with extreme caution, staying off of and well out from under steep, avalanche terrain.
current conditions

La Sal Mountains

The snow has settled into a dense, creamy cushion, and turning and riding conditions remain good in sheltered locations. Westerly winds have etched and slightly scoured exposed, westerly aspects at upper elevations. Warm temperatures have begun to affect the snow surface, primarily on sunny aspects where the snow surface has crusted over. Ridge top winds from the NW have averaged 25 mph over night with gusting into the 30's, and it is currently 25 degrees at 10,000'. There is 51" of snow on the ground in Gold Basin, and 31" at the Geyser Pass Trailhead.

Winds and temperature on Pre-Laurel Peak (11,705')

Temperature and new snow totals in Gold Basin (10,050')

Total snow depth and temperature near Geyser Pass Trailhead (9850')

Abajo Mountains

Much less snow has fallen in the Abajo Mountains with some rain falling on snow at lower elevations last weekend. No new reports of conditions have come in since last weekend, and I plan to get down there tomorrow to have a look around. Overnight winds on Abajo Peak have averaged 20 mph from the W with gusts as high as 40 mph.

Winds and temperature on Abajo Peak (11,330')

Snow totals at Camp Jackson (8968')
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

Steady, moderate, westerly winds continue to load easterly aspects at upper elevations, and dangerous wind slab conditions exist. Drifts up to three feet deep can be found, and they are connecting across wide areas. Triggering one of these slabs would be dangerous enough, but they also wield the potential to step down deeper into the snow pack causing a large, and possibly un-survivable avalanche.

The following photo illustrates persistent wind loading:
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

Snow stability tests continue to indicate that the new snow weight is dangerously close to affecting buried, persistent weak layers in the snow pack. Currently, all that is needed to trigger a large avalanche into deeper, old snow is a significant trigger. This could easily be you. In addition, steady winds have continued to ll transport significant amounts of snow, adding further weight and stress to these buried weak layers. It is a very delicate balance out there right now, and the possibility of triggering a deep, persistent slab is a very real and present danger.

Photo illustrates cracking in the snow of the past 10 days that has consolidated over top of very weak snow.

Snow pit illustrates weak layers in the snow pack with a very clean shear on mid level facets. CT12 Q3
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

Skies will be mostly cloudy today, but forecasted temperatures are expected to rise to over 40 degrees at 10,000' feet. Be alert to a rising danger for wet avalanches later in the day.

weather

Mostly cloudy skies with a high temperatures near 40 degrees at 10,000' are on tap for the mountains today. Expect continued light to moderate westerly winds along ridge tops. Saturday looks to be mostly sunny with temperatures again in the 40's.
general announcements

OBSERVATIONS: If you are out and about in the mountains, I'd love to know what you are seeing so please SUBMIT OBSERVATIONS  You can read current OBSERVATIONS HERE.

LUNA GROOMING INFORMATION: Trails are groomed and are in excellent shape. Get on them on the morning for fastest conditions.

ROAD CONDITIONS: The road is snow packed but clear.

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