The National Weather Service forecast a hazardous weather outlook for Santa Barbara and San Luis Obispo counties for late Friday night and into Saturday, bringing with it the chance of thunderstorms, gusty winds, small hail, brief heavy rain and lightning.

By noon Friday, puffy white clouds hugged the Santa Ynez Range from Ventura north through Santa Barbara and into the Santa Ynez Valley.

The change in the weather was triggered by an upper-level low-pressure system off the coast of Southern California, combined with an upper-level high-pressure system over the great basin, according to the NWS.

The threat of thunderstorms, rain and lightning was forecast to continue throughout the weekend.

The potential for dry lightning strikes and gusty winds with thunder exists through the night Friday, bringing heightened fire risks to the parched Central Coast.

By Saturday, the air mass is expected to moisten, creating an increased chance of measurable precipitation across Southern California, along with a potential for brief heavy rain, the NWS said.

The late-summer storm was expected to expand from the coastal and valley areas of Los Angeles and Ventura counties Friday evening and to areas north after midnight and into Saturday.

The threat of showers and thunderstorms will continue through Sunday morning, but by Sunday afternoon and evening should be confined to the mountains and deserts, according to the NWS.

In addition, a growing south swell could bring hazardous surf to south-facing beaches by early next week.

The NWS encouraged its weather spotters to report significant weather conditions according to standard operating procedures.

— Noozhawk staff writer Laurie Jervis can be reached at ljervis@noozhawk.com.