Indonesia moves to reinforce tsunami warning system after Flores quake

Labuan Bajo — Indonesia is moving to strengthen its tsunami early-warning system after the 15 August 2026 Flores earthquake generated tsunami waves of up to 2.5 metres in northern Flores, according to officials reporting to President Prabowo Subianto and national monitoring data from the Meteorology, Climatology and Geophysics Agency (BMKG).

The measures focus on improving disaster response and earthquake mitigation on Flores Island and nearby coastal areas, where tourism, fishing and maritime transport rely on rapid and reliable alerts during coastal emergencies.

Officials say the existing tsunami early-warning system operated quickly during the August event, issuing a warning in just over two minutes, but the government now wants to reinforce monitoring and public communication capacities.

Earthquake and tsunami on 15 August

On 15 August 2026, a magnitude 7.7 earthquake struck off Flores, East Nusa Tenggara, triggering tsunami warnings across four provinces: East Nusa Tenggara, West Nusa Tenggara, South Sulawesi and Southeast Sulawesi, according to BMKG and national media reports.

BMKG issued the initial tsunami warning around two minutes and 16 seconds after the main shock, distributing alerts through its standard channels to allow coastal communities to begin evacuation.

Monitoring stations subsequently detected tsunami waves at multiple locations. BMKG and independent assessments report maximum observed heights of about 1.6 metres at Reok in Manggarai, 0.94 metres at Maurole–Ende, and 0.36 metres at Labuan Bajo.

In a briefing to the president on 26 August, BMKG head Teuku Faisal Fathani said tsunami waves in several areas in northern Flores reached up to 2.5 metres, underscoring the need for robust warning systems and public preparedness.

Government pledge to reinforce warning coverage

Following the Flores quake and tsunami, the government announced steps to strengthen the tsunami early-warning system on Flores Island, including verification and optimisation of monitoring sensors and associated infrastructure.

BMKG reports operating around 2,000 main operational seismic sensors nationwide, with 175 in East Nusa Tenggara, supporting the Indonesia Tsunami Early Warning System (InaTEWS) used to detect earthquakes and potential tsunamis.

Officials say the system’s performance during the August quake — including the rapid warning and subsequent updates until the warning was lifted — is being studied as a key lesson for improving national disaster mitigation.

The government has also emphasised public education to reduce anxiety over aftershocks and possible further tsunamis, highlighting the importance of understanding warnings and evacuation procedures.

What is known about current coverage

BMKG tide gauges and other instruments detected tsunami waves at at least ten monitoring locations across East Nusa Tenggara, West Nusa Tenggara, South Sulawesi and Southeast Sulawesi, confirming the event and guiding warning updates.

Documented observation points include Maurole–Ende, Bulukumba, Kewapante–Sikka, Labuan Bajo, Baubau, Flores Timur, Kolaka, Sikka, Dompu and Bakalang–Alor, with wave heights generally below one metre except at Reok and Maurole–Ende.

The tsunami warning remained in force for roughly two and a half hours before BMKG declared conditions safe and ended the alert for all Indonesian territory.

Outstanding questions for coastal communities

While official statements confirm that the government intends to strengthen tsunami early-warning coverage and rely on an extensive sensor network, they do not yet specify which additional sirens, communications channels or coastal settlements will receive new or upgraded equipment.

Available reports focus on national-level performance and lessons learned rather than location-by-location details of coastal warning infrastructure in Flores, Labuan Bajo or other affected areas.

For residents, tourism operators and visitors along the Flores coast, the key confirmed development is the pledge to improve monitoring and communication after the August tsunami, while the precise technical design, geographic scope and implementation schedule of those upgrades have not yet been publicly detailed.

Sources

• Sekretariat Kabinet Republik Indonesia (English) – “Gov’t Strengthens Tsunami Early Warning System Following Flores Earthquake”
• Sekretariat Negara / Setneg (Indonesian) – “Pemerintah Perkuat Sistem Peringatan Dini Tsunami Pascagempa Flores”
• ACT Alliance / Indonesian Humanitarian Country Platform – “Earthquake and Tsunami – Flores and Surrounding Areas, Flash Update 1”
• Tempo (English) – “M7.7 Earthquake Strikes NTT's Flores, Minor Tsunami Detected”
• The Watchers – “Major M7.7 earthquake hits Flores region, Indonesia, leaving 105 ...”
• TribunFlores – “BMKG Sebut Gempa Flores Jadi Pembelajaran Penting untuk Perkuat Mitigasi Bencana di Indonesia”
• The Guardian – “Powerful earthquake kills dozens in eastern Indonesia”