The weather service had previously issued a fire weather watch for the region but upgraded it to the more serious Red Flag Warning, saying the area of greatest concern is for interior North Bay hills and mountains, particularly the Vaca and Mayacamas mountain ranges and along the border between Napa and Sonoma counties.
Dry, gusty winds arrive tonight & increase our wildfire danger. #RedFlagWarning issued for North Bay Mtns. Most critical conditions develop in Napa Co Mtns.— Mike Nicco (@MikeNiccoABC7) September 29, 2021
Positive note: much shorter duration than original Fire Weather Watch this replaces. pic.twitter.com/BSqfJtWsQu
Winds of around 15-25 mph with gusts of up to 35 mph are expected in the area, which will have low humidity overnight.
North Bay residents are bracing themselves.
"For myself and my partner, it's been a pretty big source of anxiety for us," said Aaron Weiss, who recently bought a house in Marin County's San Geronimo neighborhood.
"I grew up out here and fire danger wasn't something we really thought about at the time and I think with the impacts of climate change, even in just the past two, three years, it feels totally different being here."
VIDEO: Red Flag Warning issued for North Bay Wednesday night, National Weather Service says
Weiss had the Marin County Fire Department assess his property for fire safety. He and his partner just received a report this week with a detailed list of suggestions - clear leaf debris, remove bamboo and highly flammable juniper tree, replace a wood fence with a metal gate and natural fiber doormat with a metal or rubber mat.
"I think it's important everyone does their part to try and prevent further damage from happening during fires."
To prepare for the red flag, fire departments across the North Bay are up-staffing as best they can, given it's already been an incredibly demanding fire season.
"We brought resources back, our hand crews just came back from the Fawn Fire yesterday, so they were rehabbing their equipment today to get ready for our next fire whether it be here or anywhere in the region," said Marin County Fire Battalion Chief, Bret McTigue.
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Strong wind gusts are expected at high elevations in Marin County, but the highest fire danger will be in Napa County, where CalFire's Tyree Xander is stationed. He reminds everyone that most California wildfires are man-made.
"Everybody just be fire safe and try to limit any activities that could cause a potential fire or cause any sparks that would generate a fire as well."
On Wednesday afternoon, a grass fire broke out on Guerneville Road in Sonoma County, carried by strong winds. Luckily fire crews stopped it before it reached a barn.
VIDEO: 'It's not if, but when': North Bay conducts wildfire evacuation drill
The Santa Rosa Fire Department is also increasing staff for Red Flag fire conditions.
"We'll have ten engines in the area, allowing us to respond quicker to incidents," said Santa Rosa Assistant Fire Marshal Paul Lowenthal.
In the East Bay Hills, more than a dozen neighbors in Kensington were standing by to be wildfire watchers.
"We each take an hour or two for a 24 hour watch," said John Maccabee.
Maccabee is part of Wildcat Watch, where neighbors volunteer taking turn monitoring live Alertwildfire.org camera feeds near their homes.
The fire dispatch number is handy, if they spot anything.
EXPLAINER: What are some key decisions in fighting wildfires?
"You do everything you can to save yourself, not your things necessarily," said Maccabee.
"We've got older folks up here if a fire happened, we've got 15 minutes to get out, we are looking out for each other," said neighbor James Mahshi.
Historically, September and October is a critical time in fire season. Fire crews know because they've lived it.
"This is the time of year we see large fires, we have had rain but we still have heavier fuels in upper elevations," said Lowenthal.
The warning is set to go into effect at 11 p.m. Wednesday and expire at 11 a.m. Thursday.
Bay City News contributed to this report
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