National Weather Service United States Department of Commerce

Suicide Basin Monitoring and Current Conditions




Suicide Basin is a side basin of the Mendenhall Glacier above Juneau, Alaska. Since 2011, Suicide Basin has released glacier lake outburst floods that cause inundation along Mendenhall Lake and Mendenhall River.


Current Status: 6/29/2021: Suicide Basin drained for the first time this year on June 20th. The water level in the basin was about 200 feet lower than last year and did not produce any impacts downstream around Mendenhall Lake or River. There is still water in the basin but it is not draining at this time and the water levels are well below levels that could produce flooding along Mendenhall Lake. The basin can fill and drain through out the summer but typically the first release is the largest. NWS, USGS and UAS will continue to monitor the situation and will provide updates when needed.  


Additional Information available:




Latest Basin Image

Most recent image from the basin, updated at daily to sub-daily intervals (see time-stamp bottom right). The camera is placed at the basin entrance and faces northeast, into the basin. Click on image to enlarge and read basin levels.




Suicide Basin Lake Level
Daily updated graph tracking the lake level at Suicide Basin over the 2020 season (red line). The water level from the 2019 season is included for reference (blue line).





Last Two Week Time-Lapse

Animated time-lapse sequence, combining 15 daily images. 




2021 Last Two Week Time-Lapse Sequence With Vectors

Animated time-lapse sequence including velocity field. Color-coded arrows represent motion of the floating ice in the basin. Latest image with vectors. 






Mendenhall Lake Stage Level


Graph showing the current (blue) and predicted (purple) stage level at Mendenhall Lake. Stage levels are annotated on the left y-axis on the graph. The graph also shows the Mendenhall River discharge (right y-axis), which is derived from the Mendenhall Lake stage level via rating curve.


Once an outburst flood event begins, water levels rise at Mendenhall Lake and Mendenhall River. Drainage initiation at Suicide Basin and water level rise at Mendenhall Lake and River can be offset by several hours.





Water levels on Mendenhall River







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