Bollettino valanghe

Salt Lake

Pubblicato il Dec 12, 2020valido fino al Dec 13, 2020Utah Avalanche Center

Pericolo valanghe

Alta quota
Limite del bosco
Sotto il limite del bosco

Non aggiornato — questo bollettino è scaduto 6 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Today the avalanche danger at upper elevations will be MODERATE where winds have deposited snow. Look for and avoid these freshly formed slabs of wind drifted snow which will be small but easy to trigger. Where winds haven't drifted the new snow, it should sluff easily because the older snow underneath is very weak, faceted, and loose.

At mid and low elevations the avalanche danger is LOW.

Because the snowpack is very shallow, hitting rocks, stumps, and other obstacles remains a major concern. These hazards will be harder to see today as they will be covered by just a few inches of light snow.

Problemi valanghivi

Wind Slabs
N
NE
E
SE
S
SW
W
NW
Alta quota
Limite del bosco
Sotto il limite del bosco
Probabilità
Likely
Dimensione
1
Overnight winds from the west and southwest drifted yesterday's 2-3 inches of snow onto some slopes. Northerly winds that should increase by midday or afternoon will drift today's snow onto other slopes. Because the new snow is so light, winds will have no trouble moving this snow and forming fresh slabs of wind drifted snow.

The resulting wind slabs will be very easy to trigger because they will be resting on very weak, faceted snow that formed during the last several weeks of dry weather. Even though avalanches today won't be big, they should accelerate very quickly and sweep you off your feet. You may not get buried by these small avalanches but they could easily cause trauma. Imagine sliding downhill at 25 mph or faster and hitting a rock with your head.

What to do? Avoid these fresh wind drifts by thinking about where they form which is under ridgelines and along cross-loaded gullies. Read more HERE.

Recent Activity

No avalanches have been reported but we expect that to change in coming days.

Snow and Weather

Yesterday: 2-3 inches of low-density snow fell yesterday.

Currently: Snow started falling at 4 a.m. and 1-2 inches had fallen by 6 a.m. Temperatures range from 15 degrees F at many trailheads to 7 degrees F at 10,000 ft. Winds were blowing 15-20 mph from the west overnight but have calmed to 3-5 mph this morning.

Today: Most of the snow should fall this morning while lingering light snow showers will continue through the afternoon. 4-6 inches of low density snow should accumulate by the end of today. Winds should increase some from the northwest today and blow 20 mph at upper ridgelines.

Additional Info

Weeks of dry weather and clear, cold skies have weakened and faceted the snowpack on nearly all slopes at mid and upper elevations. The only exceptions are slopes facing due south that received direct sunshine. Even the slightest aspect change away from due south means that the snowpack is very faceted. South facing slopes with the slightest bit of shade from trees or other terrain features will have faceted snow as well.

What does this mean? Slab avalanches require 4 ingredients - slab, weak layer, steep slope, and a trigger. The old snow is the weak layer. Snow falling in coming weeks will become the slab. We are the trigger. There is no doubt that avalanches will start happening as more snow comes. The main strategy to avoid avalanches will be to avoid riding on slopes steeper than 30 degrees.

Watch the video below to learn more.

General Announcements

Please visit this website with information about Responsible Winter Recreation by the Utah Office of Outdoor Recreation.

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