SAN FRANCISCO -- An overnight of thunderstorms lit up the skies all around the San Francisco and Monterey Bay areas Tuesday, causing several power outages and triggering at least two small brushfires.

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Lightning Causes Power Outages, Ignites Brushfire

Pacific Gas and Electric Company spokesman Jonathan Fleischer said that at its height thousands of customers were without power. Fleischer reported that lightning strikes knocked out power to 6,200 customers around Livermore at about 12:15 a.m. At about 11 p.m. Monday night, he said, another lightning strike knocked out power to 1,300 customers around Morgan Hill.

The storm also knocked down wires in Castroville, he said, which blacked out 5,300 customers at 12:20 a.m. Fleischer estimated that power would be restored to most customers by early Tuesday morning.

The Contra Costa County Fire Protection District reported a 16-acre grass fire caused by a lightning strike in the mountains above Pittsburg and Bay Point along Bailey Road. That blaze was extinguished by 4:30 a.m.

The San Jose fire department reported a grass fire in the hills above Evergreen College on Yuerba Buena and San Felipe roads at 1:30 a.m. that may have been caused by a lightning strike.

The National Weather Service said the storm was triggered by an influx of "monsoonal air" from the southwest.