South Bay Quake Felt Across California Amid Recent Seismic Surge

Key points

• A magnitude 3.5 earthquake occurred at 8:40 a.m. PT on September 27, 2026, located three miles from El Segundo and four miles from Hermosa Beach.
• The U.S. Geological Survey reported the quake’s depth at 7.4 miles, with more than 1,500 people reporting feeling the shaking within the first hour.
• A second, smaller magnitude 2.6 earthquake struck approximately 20 minutes later, with shaking reported from San Jose to Walnut Creek.
• No significant damage was reported, and the event did not trigger the ShakeAlert app, which requires a magnitude of 4.0 or higher.
• The quakes occurred amid a recent uptick in seismic activity, including a swarm of 90 micro-quakes in Lennox and Westmont in September.

Background

California has experienced increased seismic activity in recent weeks, including a magnitude 3.2 earthquake along a prominent urban fault line on September 6 and a swarm of 90 micro-quakes in Lennox and Westmont on September 12. These events follow earlier warnings about the Hayward Fault and San Andreas Fault, with researchers noting higher slip rates and potential for major ruptures.

How outlets are covering it

The Los Angeles Times and LAist reported the primary quake as magnitude 3.5 and 3.6, respectively, both centered near Hermosa Beach. The New York Post reported two earthquakes, including a 3.5-magnitude event at 7:20 a.m. and a 2.6-magnitude tremor 20 minutes later, noting shaking felt from San Jose to Walnut Creek. While the LA Times and LAist focused on the South Bay impact, the New York Post emphasized the broader regional shaking and recent seismic trends. All sources agreed on the lack of significant damage and the low magnitude of the events.

Why it matters

The recent increase in low-magnitude earthquakes highlights ongoing seismic activity in California, prompting renewed attention to earthquake preparedness. While these events caused no damage, they underscore the region’s vulnerability to larger quakes, as warned by seismologists like Dr. Lucy Jones, who noted the potential for a catastrophic magnitude 7.8 rupture along the San Andreas Fault.

What to watch

Residents are encouraged to report what they felt to the USGS and review earthquake preparedness resources. Meteorologists also noted that high clouds from Hurricane Odalys may continue to produce vibrant sunsets, though no further seismic activity is predicted.