Bollettino valanghe

Salt Lake

Pubblicato il Dec 1, 2020valido fino al Dec 2, 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

Most terrain has a generally LOW avalanche danger. However, with gusts up to 90 mph overnight, areas of MODERATE danger exist at all upper elevations for triggering a stubborn slab of wind drifted snow. These wind slabs will be generally shallow and isolated to specific terrain features that allow for drifting snow to accumulate. REMEMBER that getting caught in even a small avalanche could have significant consequences with the risk of hitting a rock, stump, or downed timber.

Problemi valanghivi

Wind Slabs
N
NE
E
SE
S
SW
W
NW
Alta quota
Limite del bosco
Sotto il limite del bosco
Probabilità
Possible
Dimensione
1
Such strong overnight winds will cause any lingering soft snow to drift and form fresh slabs today. These winds drifts will be small and stubborn, as they will have had only a few inches of snow to move around, but with elevated winds, any soft snow that is available for transportation will be transported.

Look for shallow slabs of wind drifted snow on isolated upper elevation terrain features that snow could be deposited, such as ridgelines and gullies. These wind drifts can be found on all upper elevation aspects.

Look for any slopes with signs of wind drifted snow, and avoid those slopes. Wind affected snow often looks wavy, rounded, pillowy, and can sound hollow when walking or riding on it.

If you find any steep North-facing terrain features that weren't impacted by the winds the surface snow has become so weak and cohesionless that skiers and riders can to trigger "facet sluffs". While relatively small in size and predictable, any size avalanche could knock you off your feet and sweep you through dangerous terrain features.

Remember: ANY involvement in an avalanche is likely to result in traumatic injury due to the thin, early season snow cover.

Special Announcement

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

If you missed the 13th Annual Utah Snow and Avalanche Workshop, the recordings are available for purchase from the UAC Store.

The holiday season is right around the corner!! Looking for that special something for your partner? or yourself? Well, we've got an easy shopping solution for you...Buy your gifts at our Pray for Snow online auction.

Recent Activity

No new avalanches reported in the backcountry Yesterday.

Pro observer Mark White saw some small fast-running dry sluffs in in the weak faceted snow of No-name Bowl Sunday.

Video of the "facet sluffs" from No-Name Bowl (PC: M. White)

Recent observations can be found by clicking here.

Snow and Weather

This morning, under broken skies the Northwesterly winds have begun to decrease after hitting averages up to 67 mph and gusts up to 90 mph at the upper-most elevations early this morning. Temperatures are in the mid-teens at trailheads and single digits at upper elevations. The Salt Lake City area mountains picked up a trace amount of snow overnight.

Snow depths are generally 1-2', the best riding will be found on shaded north-facing terrain if you can find anywhere holding soft snow from Thanksgiving that hasn't been impacted by the strong winds. Before the winds, open North-facing terrain was developing surface hoar but that likely got knocked down overnight. The South-facing aspects have been going through a melt-freeze cycle, leading to a firm surface crust in the morning.

Today, winds will continue to decrease throughout the day as the skies become clear. The winds will continue to be Northwesterly, and elevated, gusting up to 40 mph at mid-elevations and 60 mph at upper elevations. Temperatures will be in the mid-20s F as this cold air mass stays in the area through mid-week.

Additional Info

Looking Ahead: Although our current snowpack is thin, there is widespread variability. Strong winds in the middle of November scoured many slopes, while others got a firm wind slab compressed into the terrain. Since that time, we have had several cold and clear nights that promote a "faceting" process which weakens the snowpack, turning the snow crystals into sharp, angular, weak grains. With high pressure forecast for at least the next week, this faceting process will continue.

In the long term, this weakening snow will become an issue once we get a load of storm or wind-driven snow on top of this weak snowpack structure. A perfect recipe for avalanche conditions.

Forecaster Greg Gagne gives a summary of what the snow looks like under his feet in upper Big Cottonwood on Thursday.

Weather Outlook: The longer-range models do not look particularly good for storms through mid-December.

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