The 2014 South Napa earthquake occurred in the northern San Francisco Bay Area on August 24 at 03:20:44 Pacific Daylight Time.

At 6.0 on the moment magnitude scale and with a maximum Mercalli intensity of VIII (Severe), the event was the largest in the San Francisco Bay Area since the 1989 Loma Prieta earthquake.

[7] Total damage in the southern Napa Valley and Vallejo areas was in the range of $362 million to $1 billion, with one person killed and 200 injured.

Other aspects of the event included an experimental earthquake warning system that alerted seismologists several seconds before the damaging shear waves arrived, temporary changes in springs and wells, and the potential for postseismic fault creep.

The authors of a separate study that focused on Global Positioning System data gave an estimated slip rate of 4±3mm/yr for the West Napa Fault.

[14] Several older commercial buildings in downtown Napa showed signs of extensive external damage even though many had been retrofitted for earthquake safety protection.

[22] Estimates of the damage to the wine industry were downgraded to between $80 and $100 million in a September 5, 2014, report from Silicon Valley Bank to the Napa County Board of Supervisors.

[19] CNN reported one individual still in critical condition, later discovery determined as a 58-year-old male who went through two surgeries, awakening four days later in ICU to discover it was going to take him approximately two years to learn how to walk again.

In addition, the water levels of several wells in the Sonoma Valley rose suddenly at the time of the quake, in one instance by 5 feet (1.5 m).

Earthquake warning systems could potentially give people time to take cover in the event of a quake, preventing injuries caused by falling debris, automatically stopping trains or shutting off gas lines.

The system being developed at the Berkeley Seismological Laboratory (called ShakeAlert) in conjunction with the United States Geological Survey, the California Institute of Technology and the University of Washington, will eventually cover the entire West Coast.

[42] In December 2014, United States Congress approved a $5 million allocation as part of the Consolidated Appropriations Act, 2014 in order to expand funding for development of the system.