Newest Volcano Notice Including Great Sitkin

Minor seismicity and small rockfalls were detected over the past day. Clouds obscured views of the active lava dome in satellite and webcam imagery.

The current eruption began in July 2021 and, since then, lava flows have filled most of the summit crater and advanced into valleys below. There have been no explosions at Great Sitkin Volcano since an event in May 2021. The volcano is monitored using local seismic and infrasound sensors, satellite data, webcams, and regional infrasound and lightning networks.

Low-level unrest continues with minor earthquake activity. Sulfur dioxide gas emissions were observed in otherwise cloudy satellite imagery. 

AVO released an Information Statement yesterday (June 22, 2026) summarizing the ongoing volcanic unrest from a magmatic intrusion beneath the volcano, which is also now detected in satellite ground deformation data (satellite interferometric radar or InSAR). More details can be found in the Information Statement on the AVO website: https://avo.alaska.edu/news/view/kupreanof-information-statement-june-22-2026.

There is no real-time geophysical monitoring network at Mount Kupreanof. The closest functioning seismometers are approximately 17 miles (27 km) to the east of the volcano as part of the Mount Veniaminof network. Mount Kupreanof is also monitored by satellite data, remote infrasound and lightning networks, and visual observations from pilots and mariners passing by the volcano. 

Minor seismic activity and infrasound signals were detected at the volcano. The typical degassing plume from the summit crater with sulfur dioxide and steam emissions was observed in partly cloudy webcam and satellite views. Weakly elevated surface temperatures were also seen within the summit crater in satellite imagery.

Local seismic and infrasound sensors, web cameras, and a geodetic network are used to monitor Shishaldin Volcano. In addition to the local monitoring network, AVO uses nearby geophysical networks, regional infrasound and lightning data, and satellite images to detect eruptions.