USGS Volcano Notice - DOI-USGS-AVO-2026-05-30T18:41:36+00:00

Slow eruption of lava continues. Minor seismicity detected over the past day. Slightly elevated surface temperatures were observed in satellite data. Nothing was evident in web camera observations of the volcano.

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.

Seismic activity was detected during the past day. Cloud cover prevented clear satellite views of the volcano. Sulfur dioxide emissions were detected in TROPOMI satellite data.

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 were detected at the volcano. Sulfur dioxide emissions drifting to the northwest were evident in satellite imagery. Nothing was observed in cloudy satellite and web camera views of the volcano over the past day.

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.