Six Indonesian volcanoes placed on alert, including Anak Krakatau

Six Indonesian volcanoes are on alert as activity increases, with Anak Krakatau sending ash across five provinces and forcing the closure of eight airports.

Geology Agency chief Lana Saria said Anak Krakatau erupted at 8:23 p.m. local time on September 6. Information from Indonesia’s Center for Volcanology and Geological Hazard Mitigation, the Darwin Volcanic Ash Advisory Centre and Himawari-9 satellite analysis showed ash spreading through the atmosphere toward Banten, parts of West Java, Jakarta, Lampung and Bengkulu.

Anak Krakatau, in the Sunda Strait between Java and Sumatra, has held Level III, or Alert, status since July 2, 2026. Its eruptions intensified in early September, and activity remained high on the morning of September 7. The closures affected Soekarno-Hatta, Halim Perdanakusuma, Pondok Cabe, Husein Sastranegara, Radin Inten II, Budiarto, Taufiq Kiemas and Lewoleba Wunopito airports.

“

Based on the combined eruption information and VONA from PVMBG through Magma Indonesia, the Darwin VAAC information and analysis of Himawari-9 satellite images by BMKG, volcanic ash from Mount Anak Krakatau was observed spreading through the atmosphere toward Banten, parts of West Java, Jakarta, Lampung and Bengkulu.

The other volcanoes on the list are Sinabung in North Sumatra, Semeru in East Java, Lewotobi Laki-laki in East Nusa Tenggara and Ili Lewotolok. Sinabung rose to Level III on August 31, after observations showed a thick white plume rising about 300 to 500 meters above its summit.

Semeru also recorded an eruption early in the week and was raised to Alert status. Lewotobi Laki-laki has been at Level III since May 12 and has erupted twice since August 4, with an ash column reaching 800 meters and moving west and northwest. The article also lists Ili Lewotolok as having risen to Level III on July 2.

“

An eruption of Mount Semeru occurred on Monday, September 7, 2026, at 4:50 a.m. local time.