29 July 2025, Mw 8.8, Kamchatka Peninsula, Russia Tsunami

Tsunami Events > 29 July 2025, Mw 8.8, Kamchatka Peninsula, Russia Tsunami

An earthquake at a depth of 35 km with a magnitude of 8.8 (USGS) on 29 July 2025 23:24 (UTC) offshore Kamchatka, Russian Federation, resulted in a TSUNAMI THREAT MESSAGE issued by the Pacific Tsunami Warning Center (PTWC), Tsunami Service Provider (TSP) of the Intergovernmental Coordination Group for the Pacific Tsunami Warning and Mitigation System (ICG/PTWS), 10 minutes after the event indicating the possibility of hazardous tsunami waves (based on magnitude 8.0 and depth of 74 km) for coasts located in Russia and Japan within 300 km of the earthquake epicentre.

Following consultations with the International Tsunami Information Center (ITIC) and the PTWS Steering Committee, it has been agreed that the recent event provides us with an opportunity to evaluate the performance of the system. This will enable Member States of the ICG/PTWS to identify those components which worked properly and, most importantly, what components did not work in an appropriate manner and require further attention. The Kamchatka Tsunami Post-Event Assessment (PEA) Questionnaire is planned for distribution next week through an IOC Circular Letter.

In parallel and to share experiences ITIC is organising in cooperation with the IOC Secretariat this Post Event Briefing through a webinar, on 13th August 2025 at 22:00 UTC (90 minutes). The brief will focus on the PTWS’s international and national tsunami warning and emergency response to this event. The PTWC, NWPTAC and Pacific Countries will share their responses. This will be followed by an open discussion aimed at answering country questions, and identifying priority recommendations needed to improve the PTWS and national responses. 

The M8.8 shallow reverse-faulting earthquake in the Kuril-Kamchatka Trench generated a tsunami that was observed locally and across the Pacific Basin. The great earthquake was preceded by four large earthquakes in the same location on 19 July 2025, including a M7.4 earthquake for which the PTWC and the NWPTAC issued threat messages. The 29 July 2025 earthquake was the largest earthquake since the devastating M9.1 2011 Great East Japan earthquake, and was located in the same epicentral area of the M9.0 1952 earthquake that generated a deadly local and destructive Pacific-wide tsunami with damage in Hawaii and the US West Coast.  

The Pacific Tsunami Warning Center issued its 1st Pacific Threat Message at 2333Z for Russia and Japan, and continued to monitor, issuing 24 threat bulletins for the next 26 hours until the tsunami reached the coast of Chile. The NWPTAC issued 15 regional Threat Bulletins starting from 2345Z 29 July through​ 1923Z 30 July 2025. The tsunami was recorded on five DART systems in the Northwest Pacific, and used by the PTWC to validate forecasts during the event. Waves up to 3-4 m high were observed at Vodopadnaya in southeastern Kamchatka, up to 1.74 m on sea level gauges in Hawaii, and over 1 m in California, USA, Galapagos, Ecuador and in Chile. Russia, Japan, USA, and Chile issued tsunami warnings based on the earthquake magnitude and national tsunami forecasts, prompting major evacuations. Several Pacific Island Countries issued warnings based on the PTWC and NWPTAC threat forecasts