Calif prototype quake warning system gave heads up

PASADENA, Calif. (AP) — An earthquake warning system that has been under development in California worked during this week’s light but widely felt temblor, scientists said Wednesday.

The prototype system gave 35 seconds of notice to seismologists in Pasadena about incoming seismic waves from Monday’s magnitude-4.7 quake centered in the desert in Riverside County, said U.S. Geological Survey geophysicist Doug Given, who heads the early warning effort.