UPDATE: Tsunami Advisory has been issued, replacing the Tsunami Watch for LA Area & Orange County Coastlines. The tsunami should arrive near 1AM tonight. If you are located in the coastal area, move off the beach & out of harbors & marinas. Do not go to the coast to watch.
A massive magnitude 8.7 earthquake struck off the coast of eastern Russia near Petropavlovsk-Kamchatsky on Tuesday, July 29, triggering global seismic monitoring systems and tsunami risk assessments across the Pacific Rim, including Hawaii and parts of Alaska.
Tsunami Warning issued for the State of Hawaii at: 7/29/2025, 5:43:46 PM.
California Coastline Upgraded to ‘Advisory’ as of 7:05pm PAC TIME.
Tsunami Warning The Oregon/Cal. Border – Cape Mendocino, California Issued at: 7/29/2025, 8:27:28 PM
According to the U.S. Geological Survey (USGS), the quake was caused by shallow reverse faulting along the subduction zone interface of the Kuril-Kamchatka Arc, where the Pacific Plate thrusts beneath the North America Plate at a rate of approximately 77 mm per year. Though often visualized as a single point on a map, a quake of this magnitude reflects slip across a wide fault surface — in this case, roughly 390 km long by 140 km wide.
The region is known for seismic activity and has recorded 31 significant earthquakes of M6.5 or greater within 250 km of this location in the past 100 years. Just nine days prior, a magnitude 7.4 event on July 20 was recorded nearby — now classified as a foreshock to Tuesday’s main shock.
The epicenter lies roughly 45 km southeast of the 1952 M9.0 Kamchatka earthquake, which triggered a destructive tsunami felt across the Pacific, including damage and fatalities as far away as Hawaii and Peru.
As of Wednesday, no Pacific-wide tsunami has been confirmed, but tsunami monitoring agencies across the region initiated warnings and advisories as a precaution. Hawaii was briefly under a tsunami watch, which has since been canceled following updated sea-level readings.
The Kuril-Kamchatka subduction zone remains one of the most seismically active areas in the world, and experts continue to assess the risk of aftershocks or additional seismic activity in the coming days.
This is a developing story. Further updates will be posted as new information becomes available.
