Archive · 6 Sep 2026
Anak Krakatau Eruption Sends Ash High, Closing Three Airports
Anak Krakatau is a volcano between Java and Sumatra in Indonesia.
It erupted strongly overnight and sent ash and rocks into the air.
Different news reports measured the ash cloud differently.
Some said it rose about 14 to 15 kilometers, while another report said 400 meters.
Ash caused three nearby airports to close temporarily.
Officials kept the volcano at the second-highest warning level.
People must stay at least 3 kilometers away from the crater.
Officials said the volcano was not likely to collapse in a way that would cause a tsunami.
No tsunami had been reported.
Anak Krakatau erupted overnight in Indonesia’s Sunda Strait, sending ash and rock into the sky.
Reports differed sharply on the ash plume’s height, ranging from 400 meters to about 14–15 kilometers.
Soekarno Hatta, Halim, and Lampung airports temporarily closed on September 6 because of the ash.
Authorities kept the volcano at Alert Level III and maintained a 3-kilometer exclusion zone.
Indonesia’s Geological Agency said no large collapse or tsunami threat was expected, and none had been reported.
- Who
- Anak Krakatau erupted; Indonesian volcanology and geological authorities monitored and assessed the volcano.
- What
- The volcano produced a violent eruption, ash plumes, and temporary airport closures.
- When
- The eruption occurred overnight, with airport closures lasting through the morning of September 6; seismic activity had risen since September 4.
- Where
- Anak Krakatau is in the Sunda Strait between Java and Sumatra, Indonesia.
- Why
- The airports closed because volcanic ash posed a risk to aviation.
Higher Plume Reports
Lower Plume Report
Ash-column height
Higher Plume Reports
The Watchers and La Vanguardia reported an ash plume of about 14–15 kilometers, or roughly 50,000 feet.
Lower Plume Report
NHK World reported a much lower ash-column height of 400 meters.
Number of eruptions
Higher Plume Reports
Liputan6 reported at least 10 separate eruptions.
Lower Plume Report
Tempo reported six eruptions.
Tsunami risk
Higher Plume Reports
Some reports mentioned Japan checking for tsunami risk because of Anak Krakatau’s history and the 2018 collapse-related tsunami.
Lower Plume Report
Indonesia’s Geological Agency said the volcano’s growth since 2018 remained limited and that no collapse large enough to cause a tsunami was expected.
- Volcano
- Anak Krakatau
- Location
- Sunda Strait, between Java and Sumatra
- Reported ash height
- Sources reported figures ranging from 400 meters to approximately 14–15 kilometers
- Alert status
- Alert Level III, or Siaga, the second-highest level on Indonesia’s four-tier scale
- Exclusion zone
- 3 kilometers around the crater
- Airport closures
- Soekarno Hatta and Halim until 9:30 a.m.; Lampung until 10:00 a.m. on September 6
- Tsunami assessment
- Indonesia’s Geological Agency said no collapse large enough to trigger a tsunami was expected; no tsunami was reported