Red Flag fire hazard warnings took effect at 11 pm Monday night for the North Bay hills, followed by the East Bay ridge lines at 2 am Tuesday.
Both warnings will not expire until 6 a.m. Wednesday.
The National Weather Service is concerned about low humidity and gusty winds creating conditions in which a wild land fire could quickly grow out of control.
For Marin County Fire, the warning means staffing up, and closing down some high risk public areas.
"We're a little limited on space," said Marin County Fire Captain Matt Watson, showing KTVU a small room packed with bunk beds, extra sleeping space at a Novato fire station.
The bunks are where ten members of a Marin County hand crew, seasonal firefighters, will sleep Monday and Tuesday nights.
Normally they would scatter to their homes across the Bay Area after a ten hour work day, but during a Red Flag warning, they will be on duty 24 hours.
"It is cold and late in the year and we have had some rain," said Capt. Watson, " but just because it's October and November doesn't mean we can't have big fires, because the heavier fuels are still there."
With no new rain on the horizon, the high elevations of Marin, Sonoma, Napa, and Lake Counties may experience humidity between 9 -19 percent and wind gusts between 50 and 60 mph.
PG&E is not planning any precautionary power shutdowns, as it did a few weeks ago, but plans to monitor conditions.
Mt. Tamalpais State Park and the Pt. Reyes National Seashore at Inverness will make some areas off limits for the day.
"I did come up here once before and it was closed," said hiker Natasha Zaslove, at Phoenix Lake in the Marin Municipal Water District watershed.
Zaslove wasn't aware that access would be blocked by a locked gate on Wednesday.
"I think people who hike on this trail are pretty conscientious," said Zaslove, "and I'd love if they would trust us to not start fires, but I understand they just want to be cautious."
Last October's devastating fires in Sonoma, Napa, and Mendocino Counties sparked regional change.
Local agencies are being more assertive when Red Flag warnings are issued, and establishing protocols for how and when they'll close open space to avoid an accidental ignition source.
Taking a page from the Cal-Fire playbook, fire departments are not only adding staff and keeping crews on the clock, but moving apparatus so they are available in the field and ready.
"Up-staffing of local resources, pre-positioning, is what we call it," explained Marin County Fire Battalion Chief Bret McTigue, " and it's very new, this is only the third time we've done it."
Overall staffing won't downsize until rains set-in, and with California's fire season often described as "year-round", the window to relax may be shrinking.
"We get these typical patterns in October," noted McTigue, "and some years we have a rainy October and some years we get these northeast winds, like we're having now."
The trainees joined at a very intense time, working fire after fire all summer, including two weeks at the Mendocino Complex Fire, largest in state history.
But it seemed to solidify their career choice.
"Just the brotherhood is a big part of it," said 23-year-old firefighter Foster Gutridge, of Brentwood.
"Gaining these good relationships right off the bat, spending a lot of time together and there's never a dull day."
The first and second year firefighters generally work an eight month season, from June through January.