Fire crews gained ground to keep a dangerous wildfire from burning through vineyards in Northern California’s wine country, reaching 13 percent containment of the blaze by Aug. 25, officials said.

Hot and dry conditions over the weekend helped fuel the expansive Pickett fire in Napa Valley, north of San Francisco. The fire grew to nearly 7,000 acres by Aug. 25, according to the California Department of Forestry and Fire Protection (Cal Fire).

The fire erupted at about 3 p.m. on Aug. 21 on Pickett Road in Calistoga, Cal Fire reported. Investigators were still working to determine the cause.

Firefighting crews from around the state accounted for the 2,045 personnel assigned to the fire on Aug. 25.

The flames have not damaged any vineyards or homes, Cal Fire spokesman Capt. Curtis Rhodes told The Epoch Times.

Several neighborhoods remained under evacuation orders this week, mostly because heavy-duty fire equipment has blocked many of the rural roads around the area. About 500 homes are also under evacuation warnings, Cal Fire reported.

Crews worked mostly on the east side of the fire on Aug. 24 to protect the vineyards and keep the fire away from surrounding communities, Rhodes said.

“We’re still working out there today to mitigate any threats to vineyards that lie on the east side of the fire,” he said.

Fire crews worked overnight to strengthen control lines, mop up hot spots, and protect nearby structures, Cal Fire reported in an update on the morning of Aug. 25.

The flames continue to be fueled by brush, grasses, and dead timber, which add to the growing fire intensity.

“Firefighters are working in steep, challenging terrain as they continue to strengthen containment lines,” Cal Fire stated.

Low humidity and warm weather were expected to continue, with winds picking up in the afternoon, according to officials.

California fire crews used several aircraft to help fight the Pickett fire in Napa County, Calif. (Cal Fire)

The public was also warned to not fly drones over the fire area, as it is prohibited.

Fire crews were able to push the fire back into its original footprint overnight, Rhodes said. They plan to continue work on the east side and use helicopters to fly crews into the north side. They need to cut out two miles of fire line on the north end, according to Rhodes.

The fire had been contained enough to start sending in damage assessment teams, officials reported.

The Napa Valley wine industry accounts for about 27 percent of the value of all wine produced in California. The industry contributes about $13 billion to the local economy and pays about $2.5 billion in state and local taxes, according to the Napa Valley Vintners.

More than 2,000 firefighting personnel were assigned to the blaze in Napa County, Calif. (Cal Fire)

California Gov. Gavin Newsom said the state has deployed “significant” resources to fight the fire.

“Cal Fire is working to suppress the fire as part of their routine and heroic efforts to protect communities across our state,” Newsom wrote on Facebook on Aug. 24.

Newsom is a cofounder of the PlumpJack Group, which owns PlumpJack Estate Winery, CADE Estate Winery, and Odette Estate Winery in Napa County. The governor sold his shares in the company when he became San Francisco mayor in 2004 but maintains a blind trust for the winery shares.

Newsom’s sister, Hilary Newsom, is president and partner of the PlumpJack Group.

Several air tankers from throughout the state were helping suppress the fire, aided by about 10 helicopters and nearly 70 bulldozers.

The Bay Area Air Quality Management District issued an air quality advisory because of the smoke.