A major volcanic eruption has rocked Indonesia's East Java, with Mount Semeru spewing an enormous ash column high into the atmosphere and triggering immediate evacuation efforts for vulnerable residents.
The volcano erupted at 6:11am local time on November 19, 2025, sending a massive grey ash plume soaring to approximately 54,000 feet into the sky, creating significant aviation hazards across the region.
Immediate Evacuation and Safety Measures
Emergency response teams from the East Java Regional Disaster Management Agency (BPBD) have been working tirelessly to evacuate elderly residents from affected areas, particularly in Pronojiwo District and Candipuro District within Lumajang Regency.
Mukdas Sofian, the Mount Semeru Observation Post Officer, provided crucial safety guidance, stating that residents must avoid coming within 2,500 metres of the crater due to risks of hot rock ejections.
He further warned communities about potential hazards including hot clouds, lava flows, and lahars - dangerous mudflow debris that could travel along river valleys originating from the volcano's peak.
Aviation Warnings and Ongoing Activity
The scale of the eruption prompted the Australia Volcanic Ash Advisory Centre (VAAC) to issue a red aviation warning, the highest level alert for aircraft safety in the region.
According to official statements, the volcanic activity shows no signs of abating. The pyroclastic flow continues with maximum amplitude reaching 40mm and extending up to 8.5 kilometres from the mountain's summit.
Wind patterns are currently carrying the ash cloud toward northern directions, potentially affecting wider areas as the eruption persists.
International Response and Tsunami Investigation
The Indonesian authorities have raised the alert status to level 4, the highest possible warning, indicating severe volcanic activity with potential for additional hazardous events.
In a concerning development, the Japan Meteorological Agency has initiated investigations into whether the substantial eruption could trigger tsunami activity in surrounding regions.
The Foreign Office has echoed the severity of the situation, confirming the elevated alert level and warning about the continued threat of pyroclastic flows and lava movements through river systems around Mount Semeru.
As emergency teams continue patrols and evacuation efforts, authorities remain on high alert, monitoring the volcano's behaviour closely while prioritising public safety in affected communities.
