>> Firefighters’ gains: Containment of region’s three big fires grows, but weather change could pose new problems.

The three major wildfires that have been ringing the Bay Area for two weeks continued to eat up acreage overnight Saturday and into Sunday, but containment also grew, helped by lower temperatures and the deepening reach of a thick layer of moist fog that has lingered for days.

Those conditions are expected to reverse this week as high pressure builds and brings heat, which will further dry out already tinderbox vegetation. According to the National Weather Service, temperatures will warm by 4 to 6 degrees everywhere Monday, and by the weekend it could be 10 degrees hotter in the inland areas, hitting triple digits.

Air quality is expected to remain bad, with Spare the Air Alerts issued at least through Tuesday Bay Areawide. Smoke blowing south from both the Woodward Fire in Point Reyes National Seashore and the LNU Lightning Complex fire in the North Bay has forced many people around the Bay Area to stay indoors with the windows shut.

The LNU fires, which surround Lake Berryessa, are the most contained of the three big complexes at 58%, with 375,209 acres burned as of Sunday. The SCU Lightning Complex burning in locations in five counties, including eastern Santa Clara County and southern Alameda County, is 50% contained, at more than 377,000 acres burned. The CZU Lightning Complex fire, burning in the Santa Cruz Mountains, is 35% contained at 84,640 acres burned; 300 California National Guard troops will join the CZU fire lines Monday.

But these numbers are abstractions to people who have been evacuated from their homes and don’t know when they can return or what will be there to return to.

“This morning it’s my understanding that the fire is about a quarter mile from the houses in our neighborhood. That’s pretty close,” said Madeline Hope, who lives in the hills above Point Reyes Station in an evacuation zone. For a week, she has been in nearby Seahaven, where she and her family have been staying with friends.

Hope owns a boat launch on Tomales Bay, which gives her a daily perspective on the airplanes that have swooped in and skimmed off water to take to the fire. Two planes owned by or contracted to Cal Fire have come as frequently as every 10 minutes all day at times — but not on Sunday because the smoke was too thick to safely scoop water. The plane activity is a reminder of the Woodward Fire, which is just 15% contained, at 3,000 acres burned — far smaller than the complex fires, but still upending life in many communities.

Hope wonders why she’s seen tourists venturing closer to the fire zone than she is.

“We still see visitors coming out to the area, which is just insane,” she said Sunday morning while tending to her launch.

Point Reyes Station itself is under a “status of evacuation” warning, meaning it could be evacuated at any minute, but the town still looked to be normal Sunday afternoon with people walking around and window shopping even as ash fell from the sky, which glowed orange from the nearby flames.

Bolinas saw its evacuation warning lifted Saturday.

At the SCU Lightning Complex, officials struck a cautiously victorious tone Sunday afternoon. Cal Fire Operations Section Chief Tim Ernst said crews are now focused on an indirect attack to prevent the blaze from moving farther west.

For the foreseeable future, teams will work to close off a control line between a safe dozer line on a ridge and the active fire. The smoke that’s choking the air of nearby residents is part of a controlled burn, Ernst said.

“Everything is working exactly according to plan,” he said.

Teams will continue to assess what Ernst called an “extremely complex area,” spanning a maze of deep canyons, river drainages and old, heavy fuel.

Cal Fire Deputy Chief Mike Marcucci said teams are working to get those evacuated back to their homes and that he expects to be wrapping up the SCU fire in the next few weeks.

“I look forward to getting our firefighters who have been working tirelessly on the line back to their homes, back to their families,” he said. “Because as we know, this fire season is far from over.”

At the CZU fire, which has destroyed nearly 1,300 structures in Santa Cruz and San Mateo counties, Battalion Chief Mark Brunton called Sunday a “great day of progress” and said crews are continuing to focus on the blaze’s north end.

Brunton said crews are getting a lot of calls for service during repopulation efforts because of the smoke.

“We expected that,” he said.

“We know that’s going to happen as the weather gets hotter and drier.”

Incident meteorologists said mid to late week, the winds will change to a northerly push, and residents can expect to see a significant increase in the “nuisance smoke,” Brunton said.

A total of 60,000 people remain evacuated in all three fire zones. Since the lightning siege started Aug. 15, Cal Fire has recorded 14,000 strikes causing 840 separate wildfires, many of which have merged into the three major complexes. In all, more than 1.6 million acres have burned and nearly 3,000 structures have been destroyed. There have been seven fatalities.

Two new wildfires in Southern California started over the weekend, and lightning remains a possibility in the northern part of the state and the Sierra Nevada as temperatures rise again.