Avalanche Hazard Update

Posted January 11, 6:35PM: With some clearer weather today we were able to get eyes on and utilize drone recon to further assess Juneau’s urban avalanche paths. The Behrends Avenue path has a large undisturbed pocket of snow near the summit that has yet to release and will see added stress with continued rain and elevated freezing levels. In addition, we were able to corelate a small pocket of snow that released and was responsible for a debris pile that ended near the end of Judy Lane not far from Behrends Avenue. With this assessment we have determined that if the upper slopes of the Behrends Path were to release there is adequate snow to potentially reach and damage homes along Behrends Avenue. We were also able to determine that the combination of previous slides and low amounts of snow in start zones in all other urban paths has brought the risk paths outside of the Behrends Path back down to levels acceptable for CBJ to lift the evacuation advisory and for people to return to their homes.

To be clear, CBJ is lifting the advisory in all paths except for the Behrends Path.  Unfortunately the risk in that area has not been reduced enough to recommend that residents in that area return home. As always, we will continue to monitor, assess, and inform as things progress and change.

Posted January 11 (7:00AM): Heavy rainfall and elevated freezing levels continued overnight and into this morning continuing to weaken the snowpack and keep hazard elevated. Unfortunately the situation has not changed much since the beginning of this atmospheric river rain event. Yesterday (January 10), in collaboration with AKDOT&PF we were able to utilize drone reconnaissance on some parts of the Behrends Avenue avalanche path where we did see large amounts of debris, some of which stopped just short of Behrends Avenue. Due to weather constraints we were not able to reach the upper portions of the path to determine how much has slid and what remains for future avalanches. These efforts will continue today (Sunday) as weather allows to help us determine the remaining hazard and risk.

Evacuation advisory remains in effect as we continue to monitor and assess this very dynamic and ever changing avalanche problem.

Posted January 10 (6:50PM): With reduced precipitation today avalanche activity was limited, but at least one observed avalanche deposited debris close to Behrends Avenue. With elevated freezing levels and heavy rain forecasted for tonight, the hazard will increase again and the potential for large to very large avalanches remains. The upper elevation start zones of the Mt. Juneau paths have yet to release, leaving lots of snow hanging in the balance. Temperatures from within the snowpack show that it is still cold farther down in the snowpack indicating that rain/melt water has not percolated down into some of the deeper weak layers. As water from rainfall weights this snow down and works its way through the snowpack it will test the strength of weak layers and lead to potential avalanches.

Public safety is CBJ’s top priority. The evacuation advisory remains in effect and will be reevaluated in the morning after tonight’s heavy rainfall.

Posted January 10 (7:00AM): Hazard remains elevated today (January 10) with continued rain, rising freezing levels, and moderate Southeast winds. The evacuation advisory is still in effect. A brief lull in the weather last night somewhat limited avalanche activity but is expected to ramp back up as rain continues today and freezing levels rise. As daylight approaches we will closely monitor avalanche activity and assess what has slid and what still has the potential to slide and provide updates as available. Thank you for your patience as we continue to evaluate this event while keeping public safety in mind.