Mount Semeru Erupts, Hot Clouds Flow to Gladak Perak

JAKARTA, KOMPAS - Mount Semeru in East Java erupted on Wednesday, November 19, 2025, at 4:00 PM WIB. The status of Mount Semeru was raised from Level II (Alert) to Level IV (Caution) on Wednesday (19/11/2025), at 5:00 PM WIB, just one hour after the eruption. Hot clouds have been observed striking Gladak Perak, the main bridge connecting Malang and Lumajang regencies.

The height of the Semeru eruption column reached 2,000 meters above the summit or approximately 5,676 meters above sea level. The Center for Volcanology and Geological Hazard Mitigation recommends that residents refrain from activities within an 8 km radius of the summit and avoid the southeastern area up to 20 km. PVMBG also urged residents to stay away from the banks of the Besuk Kobokan River up to 500 meters due to the presence of hot clouds and lava flows.

In a screenshot of the monitoring sent by the Head of PVMBG, Hadi Wijaya, it can be seen that a hot cloud has already struck the Gladak Perak Bridge. The bridge is located approximately 13 km from the summit of Semeru and serves as a vital traffic link between the two districts of Lumajang and Malang.

Rudi, a member of the Disaster Preparedness Cadets in Lumajang, when contacted by Kompas, stated that in the Candipuro District of Lumajang, there are 22 families taking refuge at the sub-district office. He is currently at the location to assist in the evacuation of residents.

The official PVMB page states that the observed ash column is gray with thick intensity towards the north and northwest. As this report was made at 16:00, the eruption is still ongoing.

Mukdas Sofian, in his report, outlined several recommendations, namely to refrain from any activities in the southeastern sector along Besuk Kobokan, up to 8 km from the summit (the center of the eruption).

Besuk Kobokan is the lava flow route of Semeru that stretches on the southeast side. The distance from the summit to the downstream reaches 13 km. PVMBG recommends staying away from this route due to the potential risk of being affected by the expansion of hot clouds and lava flows.

Residents are also urged to be vigilant regarding the potential for hot clouds, lava flows, and lahars along the river flows originating from the summit of Semeru, including Besuk Bang, Besuk Kembar, and Besuk Sat, as well as the small rivers that are tributaries of Besuk Kobokan.

Semeru has been continuously erupting over the past few years. For instance, in November 2025, eruptions occurred almost daily with column heights varying from 500 to 800 meters. This Wednesday afternoon, the ash column reached 2,000 meters from the summit.

The largest eruption of Semeru in the last decade occurred on December 4, 2021. At that time, the eruption resulted in the deaths of 51 individuals, injured 169 people, and left 22 individuals declared missing.

In the incident, the eruption also destroyed the Gladak Perak Bridge. The eruption generated pyroclastic flows and lahars that damaged approximately 6,000 buildings. Several villages with thousands of residents were forced to relocate to prevent fatal and mass impacts when Mount Semeru erupted again.