SAN FRANCISCO (KGO) -- Northern California is facing a potential fire threat starting Wednesday when a Red Flag Warning goes into effect from 2 p.m. to 11 p.m. The National Weather Service warns there could be "abundant lightning."
"There's nine hours, this afternoon and evening, where dry thunderstorms could initiate new fires and gusty thunderstorm winds could potentially push them around," says ABC7 News meteorologist Mike Nicco.
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"That's not the only place where we have the threat of thunderstorms," explains Nicco. "It goes all the way down the Sierra and into the high desert."
Nicco says the western Sierra Nevada and most of the northern part of the state is going to be in that same predicament Thursday.
Then as we head into Friday, the focus will be on the Sierra and other popular weekend getaways like Reno and Lake Tahoe.
"Remember the 30-30 rule if you see lightning and hear thunder," says Nicco.
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After you see lightning, start counting to 30. If you hear thunder before you reach 30, go indoors. Suspend activities for at least 30 minutes after the last clap of thunder.
"There is the potential of this continuing through the weekend," says Nicco. "We will give you an update as we get closer."
'Abundant lightning,' gusty winds could spark dangerous fires in Northern California, NWS warns