Avalanche Advisory
Advisory: Moab Area Mountains Issued by Eric Trenbeath for Friday - December 30, 2016 - 6:44am
bottom line

The avalanche danger is MODERATE on steep, upper-mid to upper elevation terrain that has a NW-N-E aspect, particularly in areas where there are deposits of wind drifted snow. Suspect the lee sides of ridge crests and terrain features such as sub-ridges and beneath rocky outcrops. Elsewhere, the avalanche danger is generally LOW.
current conditions

Today will be another mild, sunny day in the mountains. Clouds will begin streaming in this evening ahead of a closed low that is currently off the coast of Southern California. Winds will increase ahead of this system blowing in the 15-20 mph range from the SW. They are currently light, and temperatures at 10,000' are in the high 20's. Good settled powder can still be found in sheltered locations, but wind exposed slopes have sustained some damage.

Base depth in Gold Basin is 45" and the season total is 108" for 169% of normal.

Dave Garcia and I were out and about yesterday digging holes and having a good look around. For a full report from our travels go here. For a full list of recent observations go here.

Storm totals and temperature in Gold Basin.(10,000')

Wind, temperature and humidity on Pre Laurel Peak.(11,700')

Snow totals, temperature and snow/water equivalent at the Geyser Pass Trailhead. (9600')

Bluebird skies and not a breath of wind yesterday made for perfect flying conditions. A big thanks to Classic Helicopters and Bego Gerhart from Grand County Search and Rescue for delivering our rescue sled to the top of Pre Laurel Peak!

recent activity

In our travels yesterday we noticed a couple slides from the Christmas storm. One came off of the observers left side of Gravel Pit lanes (NE Face of Tukno) initiating below the chutes and then spilling over the cliffs to run the full length of Tele Gold. This slide was about 2' deep, 175' wide and ran for about 800'. We also observed a crown of similar depth below the saddle in Talking Mountain Cirque but it had blown in to the degree that other dimensions were unmeasurable. I also received a report of a significant slide in Dark Canyon.

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

You still may be able to trigger an old wind slab in upper elevation, wind exposed terrain, primarily on NW-NE-E aspects. Best tip is to suspect smooth, rounded, "fat" looking areas of wind drifted snow. Likely areas to find slabs are down slope from leeward ridge crests, and beneath terrain features such as sub-ridges or rocky buttresses. Though stubborn, if triggered they also have the potential to step down into a deeper persistent weak layer.

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

Snowpits dug yesterday showed an overall stabilization and strengthening of the snowpack. Weak layers on northerly aspects, though still present, were no longer reactive under stability tests, and a facet/crust weak layer that was very reactive on southerly aspects last week has broken down. This is good news, but with the continued presence of weak layers, I would still perform a stability analysis before jumping on to any steep slope with a NW-NE-E aspect. For a full report and snowpit profile go here.

weather

A closed low is currently moving in off the coast of Southern California bringing us a chance of snow by tomorrow and increasing by Sunday.

Today

Mostly sunny, with a high near 28. Breezy, with a southwest wind 15 to 20 mph, with gusts as high as 30 mph.

Tonight

A 20 percent chance of snow after 1am. Mostly cloudy, with a low around 13. West southwest wind 10 to 15 mph, with gusts as high as 25 mph.

Saturday

A 20 percent chance of snow before 11am. Partly sunny, with a high near 24. West northwest wind 10 to 15 mph.

Saturday Night

A 50 percent chance of snow, mainly after 11pm. Mostly cloudy, with a low around 16. Southwest wind 10 to 15 mph. New snow accumulation of 1 to 2 inches possible.

New Year's Day

Snow likely. Cloudy, with a high near 23. Breezy, with a south southwest wind 15 to 20 mph. Chance of precipitation is 70%.