Mount Semeru, located on the border of Lumajang and Malang regencies in East Java, continues to exhibit high volcanic activity. Eruption earthquakes are observed to dominate the activity of the highest volcano on Java Island, keeping its status maintained at Level III or Alert.
An officer at the Mount Semeru Observation Post, Liswanto, reported that during the observation period on Thursday (16/7/2026) from 00:00 to 06:00 WIB, 15 eruption earthquakes were recorded. These earthquakes had amplitudes ranging from 13 to 22 millimeters and durations of 71 to 158 seconds. In addition to the eruption earthquakes, five avalanche earthquakes, three emission earthquakes, one harmonic earthquake, and two distant tectonic earthquakes were also recorded.
This condition extends the streak of high volcanic activity from the previous day. Throughout Wednesday, the observation post recorded 66 eruption earthquakes. In addition, one pyroclastic flow (hot cloud avalanche) occurred with an amplitude of 22 millimeters lasting for 187 seconds, followed by 16 avalanche earthquakes.
On Thursday, Mount Semeru was also reported to have ejected a volcanic ash column 700 meters above the peak. Residents around the slopes of the mountain are urged to remain vigilant and comply with all safety recommendations issued by the authorities to avoid the threat of eruption hazards.
