Bollettino valanghe

Salt Lake

Pubblicato il Apr 5, 2023valido fino al Apr 6, 2023Utah Avalanche Center

Pericolo valanghe

Alta quota
Limite del bosco
Sotto il limite del bosco

Non aggiornato — questo bollettino è scaduto 3 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Expect the unexpected. The avalanche danger remains HIGH on all aspects and elevations today. Soft slab avalanches in the new snow are running farther and faster and breaking over wider areas than normal. These are unprecedented conditions. Avalanches will happen in the foothills not just in the canyons and higher elevations.

With so much snow, also watch out for roof avalanches near structures, and be extra cautious near tree wells or any feature where you could fall head first and be unable to get out.

Problemi valanghivi

Storm Slabs
N
NE
E
SE
S
SW
W
NW
Alta quota
Limite del bosco
Sotto il limite del bosco
Probabilità
Very Likely
Dimensione
3
There have and will continue to be soft slab avalanches occurring in the new snow that has fallen since Sunday evening. Areas with the most snow will have the greatest danger. With massive water amounts over the last week, I wouldn't be surprised to hear about avalanches breaking deeper in the snowpack.

Normally this time of year the name of the game is storm riding because snow conditions deteriorate when the sun comes out. Unfortunately, the best advice for today will be to avoid all avalanche terrain and stay far away from runout zones.

Photo below from Greg's field day in Mill Creek Canyon. It's a small avalanche on small terrain which tells us what to expect on bigger terrain.
Wind Slabs
N
NE
E
SE
S
SW
W
NW
Alta quota
Limite del bosco
Sotto il limite del bosco
Probabilità
Very Likely
Dimensione
3
Winds haven't been blowing too strong, but they have have been just right at most ridgelines to steadily transport snow and create soft slabs of wind drifted snow. Cornices are massive and are continuing to grow larger. When these break they are a significant hazard by themselves. A group found sensitive cornices yesterday above East Canyon off of Parleys Canyon. It's very risky to mess with cornices as the often break much further back than you expect - just stay away from them.

Avalanche Warning

What

The avalanche danger for the warning area will be HIGH today.

When

In effect from 6am MST this morning to 6am MST Thursday

Where

For the mountains of Northern Utah and Southeast Idaho including the Wasatch Range and the Bear River Range.

Impacts

Recent heavy accumulations of snow and drifting have created widespread areas of unstable snow. Long running natural and human triggered avalanches are likely. People should avoid being in backcountry avalanche terrain, (off of and out from under slopes steeper than 30°), and stay clear of avalanche runouts. Be careful near any structures due to roof avalanches.

Special Announcement

The report for the Pole Canyon Accident is available HERE. Thank you to the people involved for sharing so much information so that we can all learn from this accident and come home safely to our loved ones.

Recent Activity

Soft slabs of new snow were very sensitive yesterday with a widespread avalanche cycle of natural avalanches in Little Cottonwood Canyon including several close calls with avalanche professionals.

Greg was skiing in Mill Creek Canyon in a place he has traveled literally hundreds of times, and he turned around because he was triggering so many small avalanches on small terrain features where he normally doesn't see them.

Another group was skiing at low elevations near Mt Olympus (Read this ob!) and remotely triggered several avalanches up to 200 ft wide in the new snow.

Vegetation and terrain features are all buried deeply which has allowed avalanches to break wider and run further than normal.

Check out all observations HERE.

Snow and Weather

It's cold and it's still snowing. Unreal!

Overnight the Cottonwoods received an additional 7-10 inches of snow with upper LCC getting an additional 16.5 inches. Snowfall along the Park City Ridgeline varies from only about 3 inches to 12 inches overnight closer to the Canyons.

Temperatures range from the mid teens to single digits F. Winds this morning on most ridgelines are blowing from the west-northwest at 11-16 mph gusting to 23 mph. At the highest elevations, winds are gusting 33-42 mph.

I have run out of words to describe snowfall this winter. Seven-day totals of snow water equivalent are 4.3 to 5.7 inches of water in the Cottonwoods. Storm totals since Sunday evening are 35-62 inches of snow (2-3.45 inches of water).

For today, temperatures will remain cold and snowfall will continue. Lake effect snowfall should taper off this morning, but later this morning snowfall should kick in again due to convective (upward moving) atmospheric conditions. Total snowfall today is a bit uncertain but should be less than yesterday and overnight with maybe an additional 2-5 inches but more is possible. Winds will remain similar to what they are this morning.

Heads up - things may warm up considerably this weekend. Stay tuned.

Additional Info

GET READY - Conditions later this week and into this weekend will shift from cold wintry conditions to very warm spring conditions. The snowpack does not like rapid change. I don't really know what exactly to expect, but I'm certain we'll see lots of wet avalanches this weekend.

General Announcements

CLICK HERE FOR MORE GENERAL INFO AND FAQ

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.

Observations and Avalanches

Backcountry Emergency Procedures