Avalanche forecast

Moab

Utah Avalanche Center
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Avalanche danger

  • Alpine
  • Treeline
  • Below treeline
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Highlights

Heavy, wet snow and strong winds from a fast-moving atmospheric river have produced dangerous avalanche conditions in the La Sals. The avalanche danger is HIGH. A dense, cohesive slab rests on top of fragile persistent weak layers of faceted snow that formed during the November dry spell. HIGH avalanche danger exits on slopes near treeline and above that face W-N-SE. Below treeline, on slopes that face NW-N-E, the danger is CONSIDERABLE, and human-triggered avalanches are LIKELY. Avalanches failing on persistent weak layers will be three to four feet deep, taking out the entire season snowpack. All remaining slopes have a MODERATE danger for avalanches failing in the new snow.

Human-triggered avalanches are very likely, and travel in avalanche terrain is not recommended.

Avalanche problems

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Very Likely
    Size
    3

    A dense and cohesive slab is pushing a weak and fragile early-season snowpack to its breaking point. It is worth your time to scroll through the early-season observations. You will see reports of weak and faceted snow. This weak snow lies beneath the newly formed slab. In his travels yesterday, Chris Benson reported over a dozen collapses and shooting cracks up to 50 feet in length. These are obvious clues that the underlying weak snow is failing under the weight of the new snow. Keep it simple out there today, avoid avalanche terrain, and let the snowpack adjust to this massive loading event.

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    2

    Backcountry travelers should anticipate avalanches failing within the new snow and at the new snow/old snow interface. These avalanches, up to 18 inches deep, will be enough snow to push you into a terrain trap. It is possible for these avalanches to gouge down into deeply buried weak layers, causing a deeper and more dangerous avalanche.

    The six inches of snow that fell overnight was colder and drier than the foot of snow that fell early in the storm. I expect this most recent snow to produce sluffing, and loose snow avalanches on steep slopes.

    SW winds blew for the duration of the storm. There is no doubt some very dense wind slabs were deposited on lee slopes on Tuesday. The colder, drier snow from last night will complicate this situation. Gusty SW winds will have easily blown and drifted this snow into sensitive soft slabs. Be wary of fat, rounded, pillowy-looking snow. Give these slabs extra distance, as they will be especially sensitive today.

Special Announcement

We have several events coming up to kick off the winter season:

Thursday, December 5 - FREE Know Before You Go avalanche awareness talk 6 PM at the Grand County Public Library

Saturday, December 7 - 17th Annual Utah Snow and Avalanche Workshop (USAW) - Information and tickets available here.

Saturday, December 14 - 3rd Annual UAC Moab/LUNA Winter Kickoff Party, 6 PM at the MARC. Information and tickets available here.

Geyser Pass Road: 11 AM Update. Geyser Pass Road is closed for plowing. Expect the closure to last until the afternoon. It will take crews some time to clear out the very heavy snow.

Recent Activity

No recent avalanche activity has been reported.

Snow and Weather

6 A.M. Snow and Weather Data

24 Hour Snow: 12" 72 Hour Snow: 18" Season Total Snow: 44" Depth at Gold Basin: 28"

Winds on Pre-Laurel Peak: N/A Temp: 17° F Percent of Normal (SWE): 178%

Weather

The last flakes are falling in the early morning hours. It is 17 degrees in Gold Basin, we have reached our high for today and temperatures will slowly decrease, with a low of 4 degrees overnight. Pre-Laurel is offline, but other wind stations are showing overnight winds out of the SSW averaging in the 20s and gusting to the low 30s MPH. Winds will decrease, and shift to the North, blowing 10-15 MPH today as the storm exits our region. Lingering snow showers will give way to gradually clearing skies and sunshine later today. High pressure takes over, but mountain temperatures will remain cold this week. Thanksgiving should be a beautifully crisp, clear day in the mountains.

General Conditions

What a storm! This is exactly what we needed, and the real story is the water. The snow fell in two waves. The first wave was warm and wet, with heavy PI rates, dropping 12 inches of snow at 3.0 inches Snow Water Equivalent (SWE). No, that's not a typo. The second wave came overnight with colder temperatures and gave us another 6 inches of snow at 0.7 SWE for a storm total of 18 inches of snow and 3.7 inches SWE. Those are some serious water numbers! This heavy, wet snow will greatly improve mountain travel. Chris Benson reported surfing on top of everything yesterday, check out his full observation here. Early season low tide conditions still exist, and you need to be on the lookout for the usual rocks and logs, but this storm will certainly help.

The warm and wet storm has laid a cohesive slab across the mountain range. The slab rests on the many weak snow surfaces that formed during November. This is a classic strong-over-weak scenario, and it is creating very dangerous avalanche conditions. Avalanches can also fail within the storm snow, and at the new snow/old snow interface. SW winds blew throughout the duration of the storm, creating sensitive and dangerous drifts on Northerly aspects. Keep your terrain choices conservative today.

We have received a lot of great early-season observations, check them out here.

Snowpack and Weather Data

Gold Basin SNOTEL site (10,000')

SNOTEL site near Geyser Pass Winter Trailhead (9600')

Wind Station on Pre-Laurel Peak (11,400')

NWS forecast for the La Sal Mountains.

General Announcements

This forecast is from the U.S.D.A. Forest Service, which is solely responsible for its content. This forecast describes general avalanche conditions and local variations always occur.

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