Mount Anak Krakatau in Indonesia erupted on Sunday, September 6, 2026, leading to the suspension of operations at six airports and affecting hundreds of flights. Soekarno-Hatta International Airport, the primary facility serving Jakarta, suspended flight operations until 5:30 p.m. local time due to volcanic ash detected in the area.
The volcano, situated between the islands of Java and Sumatra, has been erupting since late Friday, September 4. Meteorological agency BMKG reported ash plumes reaching 20,000 feet on the Java side and up to 50,000 feet on the Sumatra side, affecting visibility in parts of Banten province.
Airport operator Angkasa Pura stated that the suspension at the Jakarta airport affected 301 flights, including 58 international routes, leaving hundreds of passengers stranded. Carriers including Singapore Airlines and Malaysia Airlines cancelled flights to and from Jakarta for the remainder of Sunday. The disaster mitigation agency (BNPB) announced plans for weather modification, such as cloud-seeding, to encourage rain to wash away the ash.
The disruption extends beyond aviation to local activities. The transport ministry reported that while ferries in the Sunda Strait remain operational, vessels must maintain a 3 km exclusion zone from the crater. For some students, school activities were cancelled on Saturday due to health concerns. The BNPB has not reported the total number of people affected by these closures or the specific economic cost to the fishing industry, which also saw cancelled trips.
The broader impact involves a heightened state of geological monitoring for Indonesia, which currently has five volcanoes—Anak Krakatau, Semeru, Merapi, Lewotobi Laki-laki, and Sinabung—at Alert Level 3. Mount Semeru also erupted on Sunday, creating an ash column 1 km high and requiring a 5 km exclusion zone. While the BNPB stated there is no immediate risk of a tsunami, the event follows the 2018 eruption of Anak Krakatau that triggered a tsunami killing more than 400 people. The transport ministry named three alternative airports—Kertajati, Ahmad Yani, and Juanda—for possible diversions.
What happens next: The BNPB planned cloud-seeding for Sunday, September 6, to clear the air. Authorities have instructed residents to remain indoors where ash is present and to use protective gear. Mount Anak Krakatau remains at Alert Level 3, a status it has held since July 2. No specific date for the full resumption of all regional flight schedules has been confirmed, as officials say it depends on the movement of volcanic ash.