Aftershocks Still Hit East Nusa Tenggara for Four Weeks, BMKG Says

RRI.CO.ID, Jakarta - The Indonesian Meteorology, Climatology, and Geophysics agency recorded 4,258 aftershocks unti Friday morning , August 21, 2026, following the M7.7 Flores earthquake. The aftershock sequence is expected to continue for another three to four weeks.

BMKG in a press release wrote 118 aftershocks were felt by local communities. Meanwhile, 31 aftershocks had magnitudes exceeding 5.0 during the same period.

BMKG Earthquake and Tsunami Director, Wijayanto, said the aftershock might continue for the next three to four weeks This was because the temporal pattern is still quite complex.

“Aftershock activity during the first few days remains relatively high, with no significant decay,” Wijayanto said.

Daily earthquake counts reached 704 events on the first day. The number rose to 746 on the second day, then gradually declined.

However, activity increased again, reaching 802 events on the sixth day. He said the sequence still showed complex temporal patterns.

Several significant aftershocks also produced intensities ranging from IV to VI MMI. Strong tremors occurred on August 19 and 20, according to BMKG monitoring.

A magnitude 5.8 earthquake on August 20 caused further damage to structures and bridges. It also triggered landslides at several locations, according to BMKG monitoring.

Relocation results showed aftershocks forming several distinct clusters across Flores. The main cluster lies north of Nagekeo near the M7.7 source zone.

Another cluster appeared north of Manggarai, west of the main source. Seismic activity also shifted dynamically between eastern and western clusters.

BMKG continues real-time monitoring around the clock throughout the week. The agency urges residents to avoid damaged buildings and remain alert.