Provo Avalanche Advisory

Forecaster: Brett Kobernik

BOTTOM LINE

Danger by aspect and elevation on slopes approaching 35° or steeper.
(click HERE for tomorrow's danger rating)


Danger Rose Tutorial

A CONSIDERABLE danger exists for triggering a shallow soft slab avalanche. Natural avalanches are not expected but human triggered avalanches are likely. This is most likely in the upper elevations where the recent two feet of new snow landed on old weak snow. Fresh wind drifting on easterly slopes should be approached with caution. Shooting cracks and collapsing are signs of an unstable snow structure.


CURRENT CONDITIONS

It's another chilly morning with most mountain locations around zero degrees and many still below zero. Winds blew snow around a bit on Wednesday and are still a little blustery with ridgetop speeds in the 10 to 15 mph range gusting into the 20s. With a fairly uneven distribution of snow across the range from the last storm and the recent wind drifting, the snow is quite variable from place to place. There are stout drifts, thinner wind crusts, soft slabs from 6 to 18" deep along with some soft powder on the surface.


RECENT ACTIVITY

No new avalanche activity was reported from the backcountry on Wednesday. Winds have stirred up the newest snow creating some fresh drifts. These would crack after being provoked but no one got any to release. A couple did collapse into old weak sugar snow. Out of the wind a very soft slab still exists overlying weak faceted snow. In these areas shear tests reveal easy and clean shears and full propagation with propagation tests (video). Underfoot, things don't feel as sensitive as they were on Monday but the weak snow showed us it's hand and does not appear to be bluffing. I'm afraid our odds aren't that good against this structure.


THREAT #1

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

My concern for today is any area where you may get one of these soft slabs to break into the weak sugary snow. This is not all cut and dry as many areas have old wind crusts interspersed with the faceted snow helping to tie things together a bit. In these areas, its harder to trigger things, more so then areas where there is just loose faceted snow under the newest load. Areas that have fresh drifting are most likely areas that have previous wind crusts making things more stubborn. Be careful as wind crusts and drifts are notorious for being inconsistent by nature.


MOUNTAIN WEATHER

We'll see clear skies with balmy temperatures into the teens today. Winds will continue from a westerly direction then slow a bit later in the day. Temperatures will warm a bit more on Friday. The focus is on a storm for this weekend with the current model run producing a good amount of water with periods of strong winds in a west and southwest flow. If this storm produces you can bet the avalanche danger will rise.


GENERAL ANNOUNCEMENTS

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The information in this advisory is from the U.S. Forest Service, which is solely responsible for its content. This advisory describes general avalanche conditions and local variations always occur.

Bruce Tremper will update this forecast Friday morning.


This information does not apply to developed ski areas or highways where avalanche control is normally done.  This advisory is from the U.S.D.A. Forest Service, which is solely responsible for its content. This advisory describes general avalanche conditions and local variations always occur.


This advisory provided by the USDA Forest Service, in partnership with:

The Friends of the Utah Avalanche Center, Utah Division of State Parks and Recreation, Utah Division of Emergency Management, Salt Lake County, Salt Lake Unified Fire Authority and the friends of the La Sal Avalanche Center. See our Sponsors Page for a complete list.