On 6 February AVO reported that satellite imagery acquired on 30 January indicated that a lava dome had grown in Cleveland's summit crater, prompting AVO to raise the Volcanic Alert Level to Watch and the Aviation Color Code to Orange. The dome was about 100 m in diameter and may have begun forming as early as 24 January when elevated surface temperatures were observed in satellite images. The size and shape of the dome appeared to be unchanged based on satellite data acquired on 2 February. Elevated surface temperatures from the lava dome were detected during 5-6 and 8-11 February.

Geological Summary. The beautifully symmetrical Mount Cleveland stratovolcano is situated at the western end of the uninhabited Chuginadak Island. It lies SE across Carlisle Pass strait from Carlisle volcano and NE across Chuginadak Pass strait from Herbert volcano. Joined to the rest of Chuginadak Island by a low isthmus, Cleveland is the highest of the Islands of the Four Mountains group and is one of the most active of the Aleutian Islands. The native name, Chuginadak, refers to the Aleut goddess of fire, who was thought to reside on the volcano. Numerous large lava flows descend the steep-sided flanks. It is possible that some 18th-to-19th century eruptions attributed to Carlisle should be ascribed to Cleveland (Miller et al., 1998). In 1944 it produced the only known fatality from an Aleutian eruption. Recent eruptions have been characterized by short-lived explosive ash emissions, at times accompanied by lava fountaining and lava flows down the flanks.

Source: US Geological Survey Alaska Volcano Observatory (AVO)