Bay Area skies boomed and flashed Thursday night with the latest gift from Mother Nature -- a fast-moving storm cell that brought thunder and lightning and is expected to dump about an inch of rain on the region as it passes.
The National Weather Service briefly issued a severe thunderstorm warning for South San Francisco, San Bruno, Pacifica, Millbrae, Daly City and Burlingame as the storm moved through.
"We saw a pretty good-sized storm cell," said National Weather Service forecaster Diana Henderson.
Flights were suspended at both San Francisco and Oakland airports, where arriving planes were held for up to 15 minutes. At SFO, thunderstorms caused delays of one to two hours, an airport duty manager said.
Mostly coastal flights have been affected by the stormy weather and travelers can expect to see delays continue throughout the night, the duty manager said.
Airport officials expect service to resume on schedule Friday morning.
Reports of lightning and thunder also came in from Berkeley, Half Moon Bay and Palo Alto, among other cities.
The weather was blamed for three power outages in Concord that affected more than 5,000 customers, most of them in the vicinity of Clayton Road. PG&E spokeswoman Jana Morris said at least one of the outages was caused by a power line that fell about 8:40 p.m., causing 1,700 PG&E customers to lose their power.
Observers later reported power out along sections of Clayton Road.
In Alameda County, expect rain and isolated thunderstorms and possibly even some hail through early Friday morning, Henderson said.
In Contra Costa County, the forecast calls for showers and thunderstorms through at least 2 a.m. Friday.
Bay City News Service contributed to this report.