Avalanche Advisory
Advisory: Moab Area Mountains Issued by Eric Trenbeath for Friday - December 11, 2015 - 6:54am
bottom line

The avalanche danger is generally LOW, but you may be some newly formed, isolated wind slabs from the strong southerly winds yesterday. Look for them on the lee sides of terrain features, in more extreme terrain above tree line on steep slopes with a N-NE-E aspect. There also still may be isolated areas where it is possible to trigger a persistent slab avalanche, primarily on steep, upper elevation slopes that face the north half of the compass. Suspect slopes with more radical terrain and distinctive terrain features such as gullies, rock bands, or convex break overs. With some new snow in the forecast, the danger could rise to MODERATE by tomorrow.




special announcement

On Saturday, December 12, UAC-Moab sponsor Moab Gear Trader, and Moab Cliffs and Canyons will be sponsoring a free beacon clinic at the new Talking Mountain Yurt in Gold Basin at 1:00 p.m. Folks can either meet at the Yurt or at the Geyser Pass Trailhead at noon. For more information call Evan from Moab Cliffs and Canyons 435-260-7066, or Marshall at Moab Gear Trader 435-355-0333.

And, the Utah Avalanche Center-Moab will be presenting a free Know Before You Go avalanche awareness presentation at the Grand County Library on Thursday, December 17 at 6:30 p.m. Call the Manti-La Sal National Forest office at 435-259-7155 fro more information.

current conditions

Mountain temperatures continue to be warm ahead of an approaching cold front and it's currently in the high 20's at 10,000' . Yesterday they made it up to right around 40 degrees. Ridge top winds continue to blow from the south, averaging 15 mph with gusting to 30. Yesterday winds really blew at times, gusting to over 50 mph, making it difficult to stand up, while carving, eroding, and transporting what snow was available.

It's now been nearly two weeks since our last snowfall which was quite low density, and the whopper of Nov. 10-11 is now a distant memory. Needless to say, it is getting a but rugged out there, and the Gold Basin snow stake has dropped to below 30" for the first time in a month. Much of the wind exposed terrain is now showing rocks, and though decent turns can still be had in the trees, stumps and dead fall are now dangerously close to the surface.

Base depth in Gold Basin: 28"

Base depth at Geyser Pass Trailhead: 18"

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



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

Yesterday, I did notice some snow blowing around in the upper elevations where strong winds were able to strip snow off of south and westerly facing slopes and deposit it somewhere down on north and northeasterly facing aspects. In most cases, these deposits will be small, isolated, and will be located far down the slope. If, for some reason you find yourself in more extreme, radical terrain, be on the lookout for stiff, smooth rounded pillows of recently deposited snow on the lee sides of terrain features such as gully walls, sub ridges, and beneath cliff bands. The danger for wind slab development could increase, particularly by tomorrow if we pick up some snow.

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

I don't think the forecasted new snow will be enough to re-activate the persistent slab danger and in general, the chances of triggering a persistent slab are unlikely. However, there may still be areas where the perfect combination exists of an old hard wind slab on top of buried, weak, sugary, faceted snow. There is also the possibility that a newly formed wind slab could be released and step down into weak sugary layers. The most likely areas for finding this problem are on steep, northerly aspects at and above tree line. Slopes with defined terrain features such as gullies, rock bands, or steep, convex break overs warrant extra caution.

weather

A fast moving system moved by to the north last night bringing us only clouds and wind. By this afternoon, the front should be over the 4 Corners giving us a shot at some snow though most of the energy appears poised to stream up through central Colorado. Another system is approaching Monday.

Today

Snow likely, mainly after 3pm. Cloudy, with a high near 29. Breezy, with a southwest wind 15 to 25 mph. Chance of precipitation is 60%. Total daytime snow accumulation of less than a half inch possible.

Tonight

Snow. Low around 19. Southwest wind 5 to 10 mph becoming north northwest after midnight. Chance of precipitation is 80%. New snow accumulation of 1 to 3 inches possible.

Saturday

A 50 percent chance of snow, mainly before 3pm. Cloudy, then gradually becoming mostly sunny, with a high near 29. Blustery, with a north wind 10 to 20 mph. New snow accumulation of around an inch possible.

Saturday Night

A 10 percent chance of snow before 11pm. Partly cloudy, with a low around 14. North northwest wind 5 to 10 mph becoming south southwest after midnight. Winds could gust as high as 20 mph.

Sunday

Mostly sunny, with a high near 33. South southwest wind 5 to 10 mph increasing to 10 to 15 mph in the afternoon. Winds could gust as high as 25 mph.

general announcements

The Road to the Geyser Pass Trailhead is plowed but snowpacked. 

Grooming equipment is ready and grooming should begin this week!

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

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.