Avalanche Advisory
Advisory: Moab Area Mountains Issued by Eric Trenbeath for Monday - December 29, 2014 - 7:01am
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There is a MODERATE ​danger for triggering a persistent slab avalanche on upper mid to upper elevation terrain steeper than 35 degrees on slopes that have a NW-N-E aspect. There is also a MODERATE danger for soft slab avalanches and loose sluffs within the new snow.




current conditions

An inch in town equals how much in the mountains? Erratic data is coming in from our snow instrumentation this morning but it looks like anywhere from 6"-10" of very light density snow has fallen since midnight. The new snow will only improve the excellent powder conditions we have been enjoying since Christmas.

The new light density snow and continued lack of appreciable winds haven't yet affected the avalanche danger, but as always, pay attention to changing conditions. An increase in wind speed will quickly move snow around forming sensitive new wind slabs on the lee sides of ridges and terrain features. Loose snow sluffing in steep terrain will be a factor today.

Our streak of miraculously calm winds continues with overnight speeds averaging 10 mph with gusts to 20 along ridge tops from the WNW. They switched to more southerly at about 1:00 a.m. and have backed off into the single digits. At 6:00 a.m. they were averaging 0 and gusting to 1.

It is 2 degrees on Pre Laurel Peak and 10 at the Geyser Pass Trailhead.

Mountain weather conditions at 11,700' on Pre-Laurel Peak.

Snow totals at Geyser Pass Trailhead.

New snow totals in Gold Basin.
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 new, light density snow will easily sluff off in steep terrain and you may also find sensitive soft slabs within the new snow. These slides will be easily manageable but they could run far and fast and have the potential to sweep you off your feet and carry you into a tree or over a rock band. Be alert to increasing winds and watch for signs of new wind slab development within the new 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

We have reached a low probability/high consequence situation with regards to persistent slab instability. November snows are turning into facets, or weak sugary snow at the ground level, and there is also a layer of weak facets associated with a crust mid pack. The snow we have received over the past couple of weeks has now largely settled into place over top of these underlying weak layers. The danger now comes with the added weight of a skier or rider triggering a slide on one of these buried weak layers. This danger is most prevalent at upper-mid to upper elevations on slopes steeper than 35 degrees that have a NW-N-E aspect, particularly in areas of rocky terrain that have a thin snowpack.

weather

The mountains should see continued periods of snow today with 2"-4" possible. High temperatures at 10,000' will be around 15 degrees with WSW winds averaging 10-15 mph along ridge tops. A closed low moving over the 4 Corners on Tuesday will continue to give us a shot of snow into Wednesday.

general announcements


Road Conditions: Plow crews will likely make it to the trailhead today so you may have to wait for them if you arrive mid morning.

Grooming Conditions: Trails have not been groomed since before the Christmas storm.

Observations: If you are out and about, I would love to know what you are seeing. Please post your observations here.

EMAIL ADVISORY  If you would like to get the daily advisory by email you will need to subscribe here.​ 

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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.