Forecast for the Salt Lake Area Mountains

Dave Kelly
Issued by Dave Kelly for
Thursday, January 11, 2024
The avalanche danger is HIGH at mid and upper elevations as new snowfall and wind-drifted snow continues to add more weight on top of a buried persistent weak layer (PWL). The avalanche danger is CONSIDERABLE at elevations below 8,000'.
Step off your sled or off the skin track and take note of any wind loading, recent avalanches, cracking, collapsing, and whoomphing as these are all signs that our weak snowpack is overloaded.
Today is a day to back off of and out from under steep terrain.
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Avalanche Warning
The avalanche danger for the warning area is HIGH for the mountains of northern and central Utah and southeast Idaho, which includes the Wasatch Range...the Bear River Range...Uinta Mountains...Manti-Skyline plateau...and the Mountains of Southwestern Utah.
Strong winds and heavy snowfall have created dangerous avalanche conditions. Avalanches failing on a widespread persistent weak layer buried under the new snow are likely. Stay off of and out from under slopes steeper than 30°.
This avalanche warning is in effect from Thursday, January 10, 2024 - 6:00am to Friday, January 11, 2024 - 6:00am
Special Announcements
Wondering what happened to the mid-pack PWL? Curious how the December dry spell will play out? Interested in what factors determine future stability trends? Please join UAC forecaster Craig Gordon at 6:00 on Thursday January 11th, at the Kimball Junction library for a FREE State of the Snowpack presentation. More INFO
Weather and Snow
Under overcast skies, trailhead temperatures are in single digits °F while the highest ridgelines are below 0 °F. Winds have blown all night from a westerly direction in the teens MPH gusting to the high 20's MPH at the 9,000' ridgelines and in the mid 20's MPH gusting to the 40's MPH with the highest gusts measured into the 50's MPH at the 11,000' ridgelines. There were reports of 4" snow/.50" water at the lower elevations and 10-14" of snow and .70/.90" water at the higher elevations in the last 24 hours. This snow has been heavily wind affected and deeper drifts can be found in exposed areas and at higher ridgelines.
For today, we are expecting COLD temperatures 9-13°F with winds blowing from the northwest 15 gusting to 20 MPH at the 9,000' ridgelines and 30 gusting to 35 MPH at the 11,000' ridgelines. Snow will continue throughout the day with 1-3" of new snow expected and up to .20" of water. There could be periods of lake enhanced showers which may bring an additional 7" of low-density snow to favored areas in Salt Lake and Ogden, particularly in the area south of I-84.

Our partners at the National Weather Service have updated the forecast and are calling for 35-50" of snow with an additional 3"-3.5" of water with a more substantial storm moving into the area Friday afternoon-Saturday.
Recent Avalanches
Yesterday, we had 8 reports of avalanches that were intentionally or unintentionally triggered from the backcountry. These were primarily on east-northeast aspects above 9,000'. I don't think a lack of reported activity at other aspects and elevations means there were no avalanches as there were reports from ski area and highway operations of avalanches failing on all aspects at mid and high elevations.
There were reports of dry-loose activity where the newest storm snow was running on a density change. These dry-loose avalanches in the new snow could entrain more snow in steep long running slopes as well as be the additional weight needed to break down in the buried PWL layer triggering a much deeper avalanche. Expect to see dry-loose storm snow avalanches today.
Photo below showing a close call with a partial burial in Mineral Fork. Thanks to the parties involved for sharing a detailed report.
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Avalanche Problem #1
Wind Drifted Snow
Type
Location
Likelihood
Size
Description
You will find reactive soft slabs of wind-drifted snow at the mid and upper elevations. It won't take much wind to transport this new snow around and any additional snow and wind could be enough to tip the scales creating avalanches failing down into the buried PWL layer from the old snow surface.
New snow drifting and loading has already been extensive enough for NATURAL AVALANCHES to have occurred in steep terrain.
Avalanche Problem #2
Persistent Weak Layer
Type
Location
Likelihood
Size
Description
This report from B. Zimmer from Day's Fork gets my attention. I have been waiting for reports to start coming in of cracking to the PWL in lower angle meadows as a pre-cursor to starting to see more natural avalanches in places where the weak layer is now overloaded by the most recent storm snow. Now that we are seeing signs of cracking and collapsing on lower angle slopes, I think we'll see and hear of more PWL related avalanche activity on steeper slopes.
Additional Information
Check out a forecaster discussion Mark and I had diving deeper into the forecast and how we will travel in the backcountry with a buried PWL

Check out this video Craig Gordon put together talking about the 5 red flags we use to determine if there is unstable snow.
1. Recent Avalanches
2. Cracking and Collapsing
3. Strong Winds
4. Heavy Snowfall
5. Rapidly Rising Temperatures
General Announcements
This information does not apply to developed ski areas or highways where avalanche control is normally done. 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.