LUMAJANG: Mount Semeru, the highest volcano on Indonesia’s Java island, erupted seven times on Monday morning, sending ash columns between 300 meters and 1,100 meters above the summit as authorities kept the mountain at Level III alert and renewed warnings for people to stay out of high risk areas. The volcano, which straddles the border of Lumajang and Malang regencies in East Java, has shown sustained activity in recent days, with officials continuing close visual and seismic monitoring from the observation post.

The largest eruption was recorded at 6:51 a.m. local time, when a white to gray ash column rose about 1,100 meters above the summit and drifted south, according to monitoring data released by the Semeru observation post. Earlier eruptions began shortly after midnight, with one of the first episodes producing an ash plume about 1,000 meters high that moved toward the southwest. Officials said seismic instruments registered the eruptions with amplitudes of up to 23 millimeters, while one event lasted more than two minutes.
Monday’s activity followed another notable eruption on Sunday morning that generated a pyroclastic flow stretching about 3.5 kilometers from the summit area. That event also sent ash roughly 1,000 meters into the air and added to signs that Semeru remained in an elevated eruptive phase heading into the new week. On Saturday, the volcano erupted nine times, with ash plumes reaching as high as 1,000 meters, underscoring a pattern of repeated emissions over several consecutive days in one of Indonesia’s most closely watched volcanic zones.
Alert level stays at III
Authorities maintained Semeru at Level III, locally known as Siaga, the second highest tier in Indonesia’s four step volcanic warning system. Residents, climbers and other visitors were told not to enter the southeastern sector along Besuk Kobokan for 13 kilometers from the summit. Officials also warned people to remain at least 500 meters from riverbanks in that corridor because hot clouds, lava and lahar flows can extend farther downstream, especially during rainfall, and to stay outside a 5 kilometer radius of the crater.
The restrictions reflect the volcano’s long record of producing hazardous ash plumes, incandescent material and fast moving pyroclastic flows. Semeru rises to 3,676 meters and is one of Indonesia’s most active volcanoes, sitting along the seismically active arc commonly known as the Pacific Ring of Fire. Its eruptions are monitored closely because communities, farms and transport links lie within reach of ashfall and river borne volcanic debris, particularly on slopes and drainage channels that have been affected in previous eruptive episodes.
Recent activity keeps officials on guard
Observation reports over the past several weeks have shown daily eruptive events at Semeru, with plumes frequently rising a few hundred meters to more than one kilometer above the summit and drifting in different directions depending on wind conditions. Monday’s eruptions fit that recent pattern, though the higher ash column recorded before dawn made the latest burst more significant than some of the smaller episodes seen earlier in the current sequence. Visual observations later in the morning were at times hampered by cloud and fog around the summit area.
Officials had not released any immediate reports of casualties or major damage linked to Monday’s eruptions, but they reiterated that communities near river channels and the southeastern flank should remain vigilant because secondary hazards can develop quickly during periods of continued activity. Local monitoring will continue around the clock as the volcano remains active, with authorities urging residents and visitors to follow the exclusion zones and official safety guidance around Mount Semeru. – By Content Syndication Services.
