Great ShakeOut earthquake drill urges preparedness for major temblor

Millions of residents in Los Angeles and Orange County -- joined by millions more across the state and globe -- took part in a "drop, cover and hold on'' exercise Thursday for the 12th Great ShakeOut Earthquake Drill, designed to encourage preparedness for a major temblor.

L.A.'s ShakeAlert app lower standards for quakes

Mayor Eric Garcetti held a news conference Wednesday to announce changes to the ShakeAlert LA app. The biggest change is that users will now be alerted when weaker quakes strike in some cases up to 45-seconds or more beforehand.