Eight Indonesian airports closed temporarily on Monday morning, September 7, 2026, after a major volcanic eruption at Mount Anak Krakatau forced widespread flight cancellations and delays across the country. Volcanic ash from the eruption disrupted airspace over Java, Sumatra, Banten, Jakarta, and West Java, leaving thousands of passengers stranded.
Flight Disruptions and Passenger Impact
Initial reports from Indonesia’s Ministry of Transportation indicated that 1,558 flights were delayed or cancelled at the eight affected airports, impacting about 170,000 passengers early Monday. Soekarno-Hatta International Airport near Jakarta was the hardest hit, with more than 900 flights connected to the airport disrupted. Later updates from Reuters raised the
total number of disrupted flights to over 2,300 and passengers affected to more than 270,000 on the same day.
Volcanic Ash Hazard and Monitoring
Indonesia’s Meteorology, Climatology and Geophysical Agency (BMKG) identified volcanic ash as the cause of airport closures, citing safety risks to aircraft engines. The ash cloud from Mount Anak Krakatau spread across key air routes, forcing authorities to close airports as a precaution. BMKG has been monitoring the ash movement continuously and issuing aviation warnings to mitigate risks. The Indonesian Geological Agency declared the volcanic alert status at Level III (Siaga), maintaining an exclusion zone around Anak Krakatau due to ongoing hazards
from volcanic material.
Traveler Consequences and Flight Schedule Variability
Passengers across Indonesia faced uncertainty and delays, with airlines cancelling or holding flights at short notice. Travelers arriving at or departing from affected airports must contend with changing flight schedules as authorities extend or review closures based on ash concentration and weather conditions. BMKG warned that airports operating normally in the morning can abruptly face restrictions should the ash cloud move into their airspace during the day.
Duration and Geographic Scope of Eruption
Mount Anak Krakatau’s eruptive episode lasted roughly 25 hours, starting late on Friday, September 4, 2026, and continuing through early Sunday, September 6. Despite the episode ending, the volcano remains
at an elevated alert level and monitored closely. Anak Krakatau is located in the Sunda Strait between Java and Sumatra islands, over 150 kilometers from Jakarta’s Soekarno-Hatta Airport, illustrating how volcanic ash can affect airspace far from the eruption site. The affected regions include Banten, Jakarta, West Java, and parts of Sumatra.
Ongoing Monitoring and Airport Closure Management
Indonesia’s authorities have avoided setting fixed reopening times for airports, instead continually assessing ash presence and weather conditions to determine safe operations. This dynamic approach addresses the unpredictability of volcanic ash movement driven by wind patterns. BMKG’s round-the-clock surveillance and coordination with transport agencies aim to ensure safety
while managing widespread travel disruption across the Indonesian archipelago.
