As of March 30th, COAC has suspended backcountry avalanche advisories and pro observations until further notice.

On March 23rd, Governor Brown of Oregon issued Stay at Home orders for the public regarding the COVID-19 outbreak. The directives are clear in that “to the maximum extent possible, individuals stay at home or in their place of residence.” On March 27th the Deschutes National Forest issued a closure of all developed recreation sites including trailheads and snoparks. COAC is committed to supporting our community, local emergency services, and agency partners and because of this we felt it important to cease operations as we all work together to minimize the impacts and spread of COVID-19.   

This decision was not taken lightly. Aside from the need to maintain congruency with the Governors' orders, there are inherent risks with backcountry activities in alpine environments and it’s important to consider unnecessary exposure to COAC forecasters, first responders, and local medical staff in light of the current situation.

We look forward to getting back into the mountains and providing you all with the tools to recreate safely in the backcountry. Until then we thank you for your continued support and wish all our mountain community the best of health and wellness.

Tumalo West Bowl Natural Wind/Strom Slab

Recent avalanche activity
Intense precipitation
Observation Date/Time:
Tue, Mar 31, 2020 - 12:40 PM
RadMaster Ryan
Three Sisters Area / 7400'
Report Type:
Snow Conditions   Avalanche Activity  
Travel Mode:
Ski or Snowboard  
Sky Conditions:
Obscured (eg: fog)
Precip Type/Intensity:
Snow / S5 Heavy snow
New Snow:
18 in
Height of Snow (HS):
24 in
Wind Direction/Speed:
W / Extreme: 38+ mph

Written Report:
Tour up East side of T-Lo from Dutchman( Closed NOT plowed 18in of wind drifted snow 4wd and high clearance a must!) at 6am. East side partner and I took turns braking trail, 14-20in of new snow on the east side. Upon reaching the ridge at approx. 7400 feet wind increased and much wind loading noted. 40mph with gusts of up to 60mph.

West Side bowl at two natural avalanches one on each side of the middle knoll. Partner and I asset that situation made document of the large cornices that formed over night 10ft plus. Both slides(left and right of knoll) appear to be a wind loaded storm slab that triggered naturally. Left side slide had a crown of 24in and ran approx. 700 ft vertical, and was 400ft flank to flank, D1, R2 in my opinion. Triggered at the top of the slope near the cornice. Right side was slightly smaller crown with less wind loading approx. 16in D1, R1.

Decision was to ski one at a time on the slide bed surface as skier compaction of the slope from last week was well known and storm slab had already ripped out. Skiing the bowl on the bed surface was still boot deep powder, skinned back up the ridge. No other evidence of snow movement. Going back down to the car on the east side proved to be challenging. Too deep to get any motion or speed. Skiing was tough, snowboard would be impossible and dangers.

NOTE My partner and I did not carpool up as to maintain social distancing and remained 6ft from each other at all times, also a good touring practice.

Avalanche Report

Avalanche Type:
SS - Soft slab
Avalanche Size (relative to path):
R3 - Medium
Avalanche Size (destruction):
D1 - Relatively harmless (10m)
Avalanche Aspect:
Avalanche Slope Angle:
Avalanche Elevation:

Avalanche Report:
See above