Description: From Reeder (1990): "During 1987, intermittent steam emissions were very common from the summit of Mount Cleveland. In addition, tephra and tephra with steam emissions from the summit were observed between 19 June and 28 August. A fairly large active lava flow, originating from the summit dome-like vent, existed on 23 through 26 June. The magmatic eruptive activity appears to have ended following a large tephra eruption of the 28 August." Reeder provides a detailed summary of the eruption observations in his report, including reports of tephra emission, a lava dome like feature's growth, lava flows, lava fountaining, lava incandescence, and reports of a detached plume up to 10,600 m that appeared to have originated at Mount Cleveland. The Smithsonian Institute (SEAN v. 12, n. 8) reports this plume height as 10,000 m.