a way to force clouds to rain over drought-stricken areas. It uses drones to fly into the clouds and disperse a small dose of chemicals, around which moisture freezes and turns into rain.

PASADENA, Calif. -- Los Angeles County is using cloud-seeding technology to coax more rain from the skies when rare storms hit parched Southern California. Bill Saunders calls himself the storm boss.

And engineers are able to aim the particles so rain will fall on sparsely populated areas and near catch basins, he said. The county had conducted cloud seeding previously but stopped because of ...