A powerful earthquake struck off Indonesia’s Flores region early on August 15, 2026. Indonesia’s Meteorology, Climatology and Geophysics Agency, BMKG, updated the magnitude to 7.7 and reported a depth of 15 kilometers. The agency placed the epicenter about 30 kilometers northeast of Nagekeo. A tsunami warning was issued for coastal areas after the earthquake and was later ended after monitoring data were reviewed.
BMKG’s updated solution
BMKG’s event record says the earthquake occurred at about 4:58 a.m. local time. The updated coordinates were 8.41 degrees south and 121.39 degrees east. The agency described a shallow event near the seafloor. Its location and magnitude prompted an initial tsunami-potential assessment. Because BMKG issued the local warning, this report uses the agency’s latest solution as the main reference for magnitude, depth, location and warning status.
Why a tsunami warning was issued
Large, shallow earthquakes beneath the sea are assessed quickly for tsunami potential because they may displace the seafloor. BMKG’s first bulletin therefore placed coastal areas around Flores under warning. The warning did not mean that a large wave was certain at every location. It was a precaution while the agency collected real-time observations from coastal stations. In a later bulletin, BMKG said that the tsunami potential had ended.
Observed sea-level changes
BMKG’s observation list recorded sea-level changes at several coastal stations. The highest value listed was 0.94 meters at Maurole-Ende. Such measurements need to be read with their station location, local coastline and observation time. After assessing data from its monitoring network, the agency ended the warning.
Why early measurements can change
Magnitude, depth and epicenter estimates released immediately after an earthquake can be revised as more seismic data arrive. Different agencies may also produce slightly different solutions because they use different station networks, data sets and calculation methods. BMKG’s updated magnitude 7.7 and 15-kilometer depth are the primary reference for Indonesia’s local monitoring and tsunami warning. Earlier figures or estimates from other institutions should not be mixed with the updated BMKG record.
What the end of the warning means
Ending the tsunami warning means BMKG no longer identified a continuing tsunami threat to the coast based on its sea-level observations. That decision is separate from other earthquake concerns, including felt shaking and possible aftershocks. People in the region should continue to follow local authorities and any new BMKG bulletins. The technical information in this report reflects the status shown in the agency’s records published on August 15, 2026.
