Avalanche Advisory

Issued: Saturday, January 13, 2018 7:30 AM Forecaster: Victor McNeil

Primary Problem

Secondary Problem


BOTTOM LINE:

Natural avalanches are possible today and human triggered avalanches are likely on upper elevation E-NE-N aspects on wind loaded slopes. We have received 1-2' of snow since Thursday, accompanied with moderate winds from the WSW and wind slabs are expected to be 1-2' deep. Caution should be exercised on slopes >30 degrees where wind slabs occur. If you trigger a wind slab it could propagate deeper into the snowpack to the various weak layers buried up to 3' deep. With warm temperatures forecasted through Monday keep an eye out for wet slide activity especially on solar aspects in the afternoon. Plan your exit strategies out of the mountains accordingly and look for roller balls, pinwheels and wet loose activity.

SPECIAL ANNOUNCEMENT:

The new beacon park at Salt Creek summit is up and running. Thanks to the Wild Horse Foundation for providing the funding. The beacon park is located near the warming shelter on the East side of the parking lot. The control box is inside a green metal stand, with instructions inside. The code is 1962. The Eastern Oregon Backcountry Festival takes place January 19-21st and is a great way to get involved with the local Wallowa Avalanche Center and help support a great organization. The Festival will take place over three days and will include a showing of TGR's "Rogue Elements" Friday night in La Grande accompanied with a fundraiser. We have some phenomenal raffle and auction items including: BCA Rescue Package, Dynafit Bindings, BCA Airbag Pack, Black Diamond gear, Da Kine goodies, Scenic Flight through Wallowas and more. Check out the following link for more details: https://www.eou.edu/outdoor/eastern-oregon-backcountry-festival-2018/ You can email Michael Hatch for more details or questions at mhatch.eou.edu

Recent Activity

Recent activity was found on ENE aspects above 7,000' yesterday in the Southern Wallowas. One slide I investigated ran on the Thanksgiving Day crust now buried down 3' in the Southern Wallowas on a ENE aspect, 7,300' on a 35-38 degree slope from a cornice failure. I observed another very large avalanche on the E Face of Cornucopia that again started at ridge line and propagated across the entire face to the valley floor. If you see avalanche activity this weekend post an observation or send me an email at victor@wallowaavalanchecenter.org

Current Conditions

Skies are mostly cloudy this morning with a few lingering snow flurries. Today we will see partly cloudy skies and mild temperatures. At 5am in the Northern Wallowas, Mt Howard was reporting 32 degrees with West winds at 11 MPH and gusts to 19. The Aneroid Lake snotel was 35 degrees with 21" of snow. The Northern Wallowas received roughly 1' of snow since Thursday. In the Blues, the High Ridge snotel was reporting 33 degrees and 28" of snow. Anthony Lakes was reporting 27 degrees, winds were not recording and 64" of snow. The Elkhorns have received 14" since Thursday. In the Southern Wallowas at Schneider Meadows it was 30 degrees with 36" of snow. The Southern Wallowas have received roughly 2' since Thursday.


Avalanche Problem #1

ASSESSMENT
Wind slabs will be found at and near ridge lines predominately on NE-E-N aspects. You should feel a density change in the upper snowpack with denser snow overriding less dense snow. Avoid slopes >30 degrees if wind slabs are present and don't over stress the snowpack by adding more than 1 skier or rider at a time. If you trigger a wind slab it could trigger weak layers buried down up to 3' in the snowpack. This is enough snow to bury you.
TREND

Same over next 48 hours
LIKELIHOOD

SIZE

Avalanche Problem #2

ASSESSMENT
Our infamous Thanksgiving Day crust with the accompanied sugar snow is now buried up to 3' deep. As this layer gets buried deeper in the snowpack it will produce less avalanche activity. It will take a greater load, or a rapid weather shift to see this layer rear its ugly head. Where you'll potentially trigger this layer is in shallower/weaker areas around rocks, trees and ridges. Don't let lack of activity on this layer lure you into complacency. This weak layer will gain strength by either getting avalanched away or by a lot more snow above it helping to insulate the weak layer, compacting it and gaining cohesion.
TREND

Same over next hours
LIKELIHOOD

SIZE

Avalanche Problem #3

ASSESSMENT
With daytime highs in the upper 30's to low 40's through Monday, expect wet avalanche activity on solar aspects up to at least 7,500'. If you begin to see pin wheels, roller balls, have to take your shirt off when your snowmobile gets stuck, then you know the snow is warming up. A loose wet avalanche could pick up enough momentum in steep terrain to create a wet slab avalanche. Choose your exit strategies accordingly as drastic temperature change is a Red Flag!
TREND

Increasing over next hours
LIKELIHOOD

SIZE

Mountain Weather


        
                
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General Annoucement

Chris Edwards will issue the next Advisory on Thursday, January 18th at 7am.


DISCLAIMER: This advisory does not apply to developed ski areas and avalanche terrain affecting highways.