Thunder, lightning and heavy rain provided a rare show for Santa Barbara County residents Sunday night.

The meteorological display came after the National Weather Service issued a flash flood warning for the northwest part of the county.

The dramatic weather may be to blame for at least one crash — in which a 12-year-old was killed — on Highway 101 near Buellton late Sunday.

A cluster of thunderstorms approached the burn areas of the Alamo and Whittier fires, moving quickly through the area while producing heavy rainfall.

Late Sunday, a second set of thunderstorms delivered another round of thunder, lightning and rain in the Santa Maria Valley.

A flood advisory was issued for the Sherpa and Whittier burn areas due to the widespread rain and wind potentially causing debris flows, authorities said.

The storms also dumped heavy downpours on the Santa Maria, Orcutt, Los Alamos and Sisquoc areas.

On Highway 101 near Mariposa Reina on the Gaviota coast, lightning reportedly struck a power pole, setting a transformer on fire, according to emergency dispatch reports.

Lightning was visible over the Santa Barbara Channel, and thunder was heard throughout the South Coast, which also experienced scattered downpours.

Lightning above the Santa Barbara Channel on Sunday night. (Mike Eliason photo)

At 9:45 p.m., the National Weather Service was reporting thunderstorms across the county, with strong wind gusts to 50 mph, dime-size hail, frequent lightning and heavy downpours.

Santa Barbara County firefighters were checking a report that a second utility pole was struck near Gaviota State Beach.

Inland areas also had flash flood warnings, including the Cuyama Valley, Lockwood Valley in Ventura County and southeastern San Luis Obispo County.

Authorities reminded residents to “turn around, don’t drown when encountering heavy floods.”

Most deaths related to flooding occur among people in vehicles, authorities said.

Mariners were warned about wind gusts creating rough seas, lightning, heavy downpours, small hail and waterspouts. They were urged to seek safe harbor due to the hazardous conditions.

At one Santa Maria Valley gauge, the rainfall as of 11:30 p.m. amounted to .21 inch, while Lompoc City Hall recorded .23, Los Olivos got .25, Hollister Ranch saw .51, Santa Barbara Portrero saw .72 and Bates Ridge received .32, both of which are in the Santa Barbara County mountains.

At 9:45 p.m., radar showed thunderstorms across Santa Barbara County, with lightning, thunder, hail, gusts to 50 mph and scattered downpours. (National Weather Service radar)

As occurs with thunderstorms, “a lot of it missed a lot of areas,” said Stuart Seto of the weather service.

The monsoonal moisture was expected to linger into Monday, with a 50-percent chance of showers and thunderstorms overnight in Santa Barbara County.

Some thunderstorms may produce gusty winds and small hail, the weather service said.

Monday’s forecast calls for mostly cloudy skies with a 20 percent chance of showers and thunderstorms in the morning, then partly cloudy in the afternoon for Santa Barbara.

High temperatures will be in the 80s for most areas and cooler at the beaches.

In the North County, Monday’s forecast calls for mostly cloudy skies with a chance of showers and a 30-percent chance of thunderstorms in the morning, then partly cloudy in the afternoon.

Highs should range from the upper 60s to mid-70s at the beaches to the upper 70s and 80s inland.

— Noozhawk North County editor Janene Scully can be reached at jscully@noozhawk.com. Follow Noozhawk on Twitter: @noozhawk, @NoozhawkNews and @NoozhawkBiz. Connect with Noozhawk on Facebook.

Lightning above the Santa Barbara Channel on Sunday night. (Mike Eliason photo)