Logan Avalanche Advisory

Forecaster: Toby Weed

BOTTOM LINE

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


Danger Rose Tutorial

There is a level 2 or Moderate danger in the backcountry, and heightened avalanche conditions exist in many areas. There are also pockets with a level 3 danger in some upper elevation terrain exposed to wind drifting.... Avoid and stay out from under large overhanging cornices on the ridgetops, some of which might naturally fail and many that are likely to break further back than expected.. These or you could trigger fresh or older stiff wind slabs on drifted slopes steeper than about 35 degrees. Dangerous triggered deep slab avalanches are possible in areas with a poor snow structure and/or a shallower slab layer, and could be triggered by overrunning snow from wind slabs or cornice fall. The danger of wet avalanches will rise with midday warming, especially when the powerful spring sunshine breaks through the cloud cover causing the saturated surface snow to soften. Continue to use safe travel protocols and evaluate the snow and terrain carefully.


CURRENT CONDITIONS

Strong west winds continued with the fast moving storm overnight, which looks to have brought rain and a few inches of heavy snow to the Central Bear River Range overnight...The Tony Grove Snotel at 8400' reports 24 degrees this morning, and the station picked 8/10ths of an inch of water in the last 24 hrs. The the total depth remained at 119 inches overnight and the station sits at 145% of normal water content for the date.


RECENT ACTIVITY

The rapid warm up yesterday caused many natural loose wet avalanches locally, mainly on sunny mid-elevation slopes... Snow safety teams in the Ogden Area Mountains report triggering a few wet slabs below 8000', and another scary deep slab was intentionally triggered in the Central Wasatch... A snowboarder unintentionally triggered a wind slab avalanche southwest of Tony Grove Lake on Wednesday. The avalanche on a northeast facing slope at around 9000' was reported to be around 60 feet wide and 1 to 2 feet deep...

.See our avalanche list HERE


THREAT #1

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

Avoid and stay well away from and out from under the huge overhanging cornices on the major ridge lines, which often break further back than expected and are likely to trigger avalanches on steep slopes below. Strong winds yesterday and overnight with some heavy snow continued to build these monsters and at the same time, warming temperatures are causing them to soften, sag, and buckle. Large natural and triggered cornice falls are possible this weekend.

West winds picked up yesterday and remained strong through the night, building drifts and wind slabs with fresh and falling heavy snow in exposed terrain... Older wind slabs from earlier in the week built on lighter density, colder snow and in some cases, a thin frosty weak layer or surface hoar. Watch for and avoid drifted, stiffer snow on steep slopes on the lee sides of ridges and around terrain features like under cliff bands, gullies, or roll-offs.


THREAT #2

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

Dangerous triggered deep slab avalanches, failing on now deeply buried January weak layers are possible in some areas, more so with the recent load of new snow, wind drifting, and rapidly warming temperatures. Overrunning snow from cornice falls or fresh wind slabs triggered several of the most recent natural hard slabs in the zone, and this scenario is possible again this weekend. The seasonally warming temperatures are likely softening the existing hard slabs, which may allow for human triggering in some cases.....


THREAT #3

WHERE PROBABILITY SIZE TREND
      Over the next 10 hours.

Temperatures remain above freeing at lower elevations and have only dropped below freezing at many mountain locations in the last few hours. The overnight cooling should have refrozen the moist snow surface in most areas, but seasonal midday warming and potential green-housing today will again cause the saturated surface snow to soften and become prone to wet avalanche... Loose wet avalanches will be most likely on steep slopes with soft saturated snow, but more dangerous wet slabs are also possible, mainly in sunny terrain below around 7500' in elevation.


MOUNTAIN WEATHER

We'll see continued snowfall at upper elevations this morning, but clearing and fairly warm temperatures this afternoon... The moist westerly flow will continue, with cloud cover building in again overnight and a chance for more snow..... Looks like the weather pattern will continue through the weekend, with cooler temperatures tomorrow and Sunday and periods of snowfall, although not much accumulation is expected...


GENERAL ANNOUNCEMENTS

We are offering a free avalanche awareness talk for riders on Thursday, March 24 at 6:00 at Renegade Sports in Nibley. This will be followed by a ride into avalanche terrain (field session) on Saturday, March 26.....

You can view a photo summary of last year's avalanche activity in the Logan Area HERE

Join the friends of the Utah Avalanche Center in Logan on facebook. Click HERE

I will update this advisory in the mornings on Mondays, Wednesdays, Fridays, and Saturdays, and on other days if backcountry avalanche conditions warrant...

You have the opportunity to participate in the creation of our own community avalanche advisory by submitting avalanche and snow observations. You can also call us at 801-524-5304 or Toby at 435-757-7578, or email by clicking HERE

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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 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.