Alaska Volcano Observatory

No significant changes seen at Great Sitkin Volcano where lava continues to slowly erupt within the summit crater. Over the past day, a few earthquakes were detected beneath the volcano. Satellite and web camera views of the volcano have been obscured by clouds.

The current lava flow eruption began in July 2021. No explosive events have occurred since a single event in May 2021.

Local seismic and infrasound sensors and web cameras are used to monitor Great Sitkin along with regional infrasound and lightning networks and satellite data.

No major changes have occurred in the last day at Shishaldin Volcano where minor volcanic unrest continues. Small, low-frequency earthquakes and seismic tremor are occurring and during periods with low wind, minor infrasound signals are detected, possibly coming from very small explosions occurring deep in the volcanic conduit. Satellite and web camera views of the volcano have been obscured by clouds.

Minor rock falls associated with gravitational collapse of the unstable ground in and near the summit crater may occur without warning. The collapse events can generate small clouds of dust likely composed of fine-grained ash. The diffuse dust clouds dissipate quickly and can produce irregular-shaped deposits near the summit. The last significant ash-producing eruption occurred in November 2023. 

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 lighting data, and satellite images to detect eruptions. 

In response to elevated sulfur dioxide gas emissions detected over the past couple of week, the Alaska Volcano Observatory upgraded the Aviation Color Code to YELLOW and Volcano Alert Level to ADVISORY yesterday afternoon. No significant signs of unreset were observed over the past day. Seismicity has been quiet and no explosions were detected by infrasound sensors.  Nothing unusual was observed in satellite data and steaming from the summit vent was seen in web camera images.

Episodes of lava effusion and explosions can occur without advance warning. Explosions from Mount Cleveland are normally short-duration and only present a hazard to aviation in the immediate vicinity of the volcano. Larger explosions that present a more widespread hazard to aviation are possible but are less likely and occur less frequently.

Cleveland volcano is currently monitored by a local seismic network, infrasound sensors, a gas sensor and web cameras. In addition to the local monitoring network, AVO uses nearby geophysical networks, regional infrasound and lighting data, and satellite observations to detect eruptions. Based on past events, explosive eruptions of Cleveland may occur with little or no warning. Rapid detection of an ash-producing eruption may be possible using a combination of seismic, infrasound, web camera, lightning, and satellite data.