Forecasters said the areas expected to have particularly windy conditions and low humidity include the North Bay interior mountains, the East Bay hills and Diablo Range, and the San Francisco Peninsula.
TIMELINE: Light rain tomorrow before Red Flag Warning with high fire danger later this week
"Well historically this is our most dangerous point of fire season," said Oakland Battalion Chief Anthony Sanders.
There have been a couple fires so far this year but nothing that's gotten out of control in the East Bay Hills. However, the Fire Weather Watch that has now turned into a Red Flag Warning has fire departments on high alert with the worrisome combination of gusty winds, low humidity and warm temperatures expected late Thursday.
"Now that we're having the offshore winds with the fuel that's already been dried out, that's what concerns us is the wind patterns and the dry vegetation we have," said Chief Sanders.
The recent heat wave didn't help.
"We'll be gearing up tomorrow based on spot weather forecast results. Depending on the results, that can trigger upstaffing on our part, community messaging," said Berkeley Fire Chief David Sprague. "We're not anticipating calling for people to leave the hills early which is what we'd call for in the most extreme fire weather days."
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"I know there are talks at the county level about doing strike team prepositioning. We stage them centrally in the county - usually in the Dublin-Pleasanton area so as soon as something happens we can send those resources right away," said Chief Sanders.
Oakland Fire is actively upstaffing with extra engines and personnel positioned in the hills.
Fire officials are asking people to sign up for alerts and have evacuation plans mapped out in advance. Starting Thursday they're urging a high level of caution.
"Be careful of barbequing, idling cars, anything that's a heat producing appliance during this period of time," said Chief Sprague.
Meanwhile PG& E is warning that power shutoffs are possible throughout much of the Bay Area on Thursday, Friday and Saturday because of concerns the winds could spark fires.
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