LOS ANGELES -- The National Weather Service has issued a flash flood warning for parts of Kern, Riverside and San Bernardino counties Thursday.

A flash flood warning means that flooding is imminent or occurring.

Extreme weather conditions first struck the Southland Wednesday, bringing triple digit temperatures to the valleys and deserts as well as thunderstorms and lighting, which sparked several fires and flash floods in the mountain and inland areas.


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Lightning ignited three small brush fires near Tehachapi around 6 p.m. Wednesday.

Several outbuildings were burned, but no structures were threatened, according to the Kern County Sheriff's office.

Firefighters were able to contain those blazes by Wednesday night, but they remained on alert in the area.

Spot fires were also reported in Temecula and Perris and in Lake Elsinore, where the storm system knocked down power lines.

In Lake Elsinore, electrical lines fell on an RTA shuttle bus carrying about a dozen passengers after a lightning strike knocked down a power pole.

The passengers were trapped inside while the electrical lines were live.

Southern California Edison crews were able to cut off the power and the passengers were safely rescued.

In Palmdale, thunderstorms and spot fires were reported while on Highway 14, drivers dealt with a surprise hail storm.

Heavy rain flooded the main road into the mountain town of Forest Falls off Highway 38 above Redlands, according to the CHP.

Trees, boulders and dirt blocked the road but no motorists were stuck.

In southern Kern County, firefighters were attacking a 1,300-acre wildfire that temporarily forced evacuation of 200 rural homes on Tuesday. The fire near Lebec was 60 percent contained Wednesday.

Closer to the metropolitan area of Los Angeles, residents dealt with high temperatures, similar to the ones felt on Tuesday.

Downtown Los Angeles had moderate, midday highs in the low 80s, while the San Fernando Valley sizzled in the high 90s.

Coastal temperatures were in the 60s and 70s, but a big Southern Hemisphere swell triggered advisories for high surf and dangerous rip currents on south-facing beaches from Los Angeles to San Diego.

The heat wave is expected to stick around through Friday, with cooler temperatures moving into the area by the weekend but things could heat up again next week, according to the NWS.