Mount Semeru Erupts Again as Hot Cloud Height Reaches 2 km

Mount Semeru in East Java erupted again at 7:07 PM WIB on Friday (29/5). The volcanic ash column was observed reaching approximately 2,000 metres above the peak, or about 5,676 metres above sea level. ‘The ash column was observed in white to grey hues with thick intensity drifting towards the southeast,’ said Lana Saria, Acting Head of the Geological Agency, in the official PVMBG report cited by detikJatim on Friday (29/5/2026). The eruption was clearly recorded on seismograms with a maximum amplitude of 22 mm. As of the report, the duration of the eruption tremor was recorded at approximately 3 minutes and 51 seconds. The volcanic activity also triggered a pyroclastic flow, with hot material moving towards the southeast sector. ‘A pyroclastic flow occurred towards the Besuk Kobokan area in the southeast, with a travel distance of 2,000 metres. The eruption was ongoing at the time of the report,’ the agency added. Mount Semeru’s status remains at Level III (Siaga). PVMBG issued three key recommendations that the public must adhere to for safety. Residents are prohibited from any activities in the southeastern sector along the Besuk Kobokan river within 13 km of the peak. They are also banned from activities within a 5 km radius of the crater or peak due to high risk of hot rock ejections.