An 8.8-magnitude earthquake in the Banda Sea near Russia's Kamchatka Peninsula on July 30, 2025, prompted tsunami and advisory alerts throughout the Pacific, including the American West Coast.
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| Tsunami Warning for California's Coast |
Current Situation
Tsunami Warning for Northern California (from Cape Mendocino northward to the Oregon border). Potential wave heights: 3–5 feet, with the highest risk in Crescent City.
The rest of the California coast—from the California–Mexico border through Cape Mendocino—is under a Tsunami Advisory, with powerful currents and dangerous waves expected. (Tsunami.gov)
Estimated wave arrival times for selected California locations:
Crescent City: ~11:50 PM PT
Monterey: ~12:15 AM
San Francisco: ~12:40 AM
Los Angeles Harbor: ~1:05 AM (Los Angeles Times)
Dangerous currents and surges could continue for 10 to 36 hours after the first wave, and the first wave may not be the largest. (Los Angeles Times)
What Do These Alert Levels Mean?
According to the U.S. Tsunami Warning Centers:
| Alert Level | Meaning | Recommended Action |
|---|---|---|
| Warning | Dangerous coastal flooding and strong currents | Move inland or to higher ground immediately |
| Advisory | Strong waves & currents unsafe near shore | Avoid ports, harbors, and beaches |
| Watch | Tsunami possible; conditions being evaluated | Stay tuned for updates; be ready to act |
| Information | No significant tsunami hazard | No action needed |
What California Residents Should Do
-
Northern California (Humboldt or Del Norte counties):
Under a Tsunami Warning—evacuate coastal areas immediately. (Los Angeles Times) -
Elsewhere along the California coast:
Under a Tsunami Advisory—avoid beaches, marinas, and harbors. Do not go near the water. (CBS News) -
Boaters and vessel owners:
Move vessels to deep water or secure them in safe harbor. Follow instructions from local maritime officials. (CBS News, weather.gov) -
Stay informed:
Monitor local authorities, the National Weather Service, and NTWC/PTWC updates. (en.wikipedia.org)
Why Crescent City is So Vulnerable
Crescent City has a long history of tsunami impacts:
Severe damage from the 2005 and 2011 tsunami waves, including harbor destruction and fatalities. (en.wikipedia.org)
The harbor was rebuilt with Dolos armor blocks to withstand future events. (en.wikipedia.org)
Despite preparedness plans, Crescent City remains highly exposed. (San Francisco Chronicle)
Timeline of Events
July 30, 2025 (UTC): Magnitude 8.8 earthquake off Kamchatka triggers warnings across the Pacific. (AP News)
Within hours: Tsunami waves hit Severo‑Kurilsk, Russia; Japan sees first waves and begins evacuations. (AP News)
U.S. Actions:
Hawaii declares emergency and begins evacuations.
West Coast placed under Tsunami Watch, later upgraded to Advisory and Warning as data confirmed the threat. ( The Guardian , Los Angeles Times)
Preparedness & Monitoring Tech
Tsunami warning systems rely on:
DART buoys and sea-level stations that detect pressure changes and send data via satellite. (en.wikipedia.org)
National and Pacific Tsunami Warning Centers (NTWC/PTWC) that analyze seismic activity and sea-level changes to issue alerts and official guidance. (en.wikipedia.org)
Stay Safe: Key Takeaways
Northern California (Cape Mendocino to Oregon border): Under a Tsunami Warning— evacuate coastal zones immediately.
Rest of California coast: Under a Tsunami Advisory—stay away from beaches, harbors, and marinas.
The first wave may not be the largest—remain alert for hours.
Follow instructions from local emergency officials and stay updated through NOAA and NTWC/PTWC.
Obey all evacuation orders and warning sirens.
