Forecast for the Logan Area Mountains
Issued by Toby Weed on
Monday morning, December 9, 2019
Monday morning, December 9, 2019
Areas with CONSIDERABLE danger exist on drifted slopes at upper elevations. Avalanches are likely today in drifted terrain, and a person could trigger a large and dangerous avalanche failing on a persistent weak layer of loose sugary snow near the ground on some upper elevation slopes facing northwest, north, northeast, or east. Safer conditions can be found at lower elevations and in sheltered terrain.
- Evaluate snow and terrain carefully. Use caution while route finding, and make conservative decisions.
- Avoid steep wind drifted slopes.
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Learn how to read the forecast here
Weather and Snow
It's 23°F at the 8400' Tony Grove Snotel this morning, and there is 7 inches of heavy new snow, containing .9" SWE from the last 24 hours. I'm reading 34 inches of total snow containing 101% of normal for the date. It's 17°F at the 9700' CSI Logan Peak weather station, and northwest winds are diminishing a bit and are blowing about 15 mph, after sustaining average wind speeds in the 20s overnight. Sustained west and northwest wind yesterday and overnight caused an increase in danger of avalanches involving wind drifted snow. Areas with dangerous avalanche conditions exist on upper elevation slopes facing east, northeast, north, and northwest, where people could trigger large and scary avalanches failing on a buried persistent weak layer near the ground.
Expect snow showers to taper out this morning, and it'll be mostly sunny today. 8500' high temperatures will drop to around 16°F by evening, and 9 to 13 mph northwest winds will blow along the ridges. It'll be mostly cloudy in the mountains tonight, with low temperatures around 13°F, but rising during the night to around 21°F. Calm winds will become 5 to 8 mph from the west after midnight. It'll be partly cloudy tomorrow, with high temperatures around 22°F, and 5 to 7 mph southwest winds. The next round of winter weather is expected around Thursday, with growing potential for a decent storm for the weekend.
Recent Avalanches
Two riders were caught and carried, and one of them was partially buried in an avalanche just north of the Idaho State Line on Saturday afternoon. Here's the report.
Tuesday, a solo skier unintentionally triggered a good sized avalanche failing on the sugary persistent weak layer near the ground in the west half of Miller Bowl south of Tony Grove Lake. The avalanche on a north facing slope at around 8700' was around 2' deep and at least 150' wide. report is HERE
Avalanche Problem #1
Persistent Weak Layer
Type
Location
Likelihood
Size
Description
Most sunny slopes were bare and many others patchy or crusty after the prolonged November dry spell. But on shady slopes above about 8000' the old October snow has grown sugary and very weak. Dangerous and destructive avalanches failing near the ground are possible, and the danger on many of these slopes will persist for a while. The snow is gradually becoming more stable, but avalanches on some slopes could still be triggered remotely, from a distance, or below!
- Cracking and collapsing are red flags indicating unstable snow conditions.
Avalanche Problem #2
Wind Drifted Snow
Type
Location
Likelihood
Size
Description
West and northwest winds sustained average speeds in the 20's on Logan Peak yesterday and overnight. Yesterday's heavy snow was drifted into lee slope deposition areas. Drifts or wind slabs are likely to be sensitive to human triggering today, so as usual, avoid steep slopes with recently drifted snow.
- Even small avalanches can be very dangerous in shallow snow conditions, because you could be dragged into rocks or stumps.
Additional Information
Thanks to the generous support of our Utah ski resorts and Ski Utah, we have discount lift tickets available. All proceeds from these go towards paying for avalanche forecasting and education! Get your tickets HERE.
Need a Christmas present for your favorite backcountry partner? Get one of these cool t-shirts to support the UAC and other avalanche centers across the U.S. HERE
General Announcements
The Tony Grove Road is not maintained for wheeled vehicles in the winter, and it is snowpacked, narrow, and icy in places. You could easily get stuck in deep snow, and it doesn't look like anyone was able to drive very far up recently. Hikers, cross country skiers, snow bikers, dogs, sleds, and 4x4s share the road this time of year, so be nice and keep your speed down around others.
It's key to head into the early avalanche season with the proper mindset. In this podcast, we talk with UAC program director Bo Torrey. Bo talks about particular risks unique to the early season, tips and tricks for knocking the rust off your early season rescue skills, and charts out the path forward with avalanche education. HERE