Tens of thousands of residents have been evacuated from towns including the entirety of wine tourism destination Calistoga

Two California wildfires that ravaged Napa's famous wine region and killed three people exploded in size Tuesday as firefighters faced a weeks-long battle to contain the blazes.

The so-called Glass Fire enveloping some of northern California's world-famous vineyards has scorched 42,000 acres (17,000 hectares) and remains zero percent contained, despite the efforts of some 1,500 firefighters.

Celebrated Napa wineries such as Chateau Boswell and part of Castello di Amorosa have been lost to the flames, which reached the fringes of Santa Rosa—the largest town in neighboring Sonoma County.

Tens of thousands of residents have been evacuated from towns including the entirety of wine tourism destination Calistoga.

"It looks like a bomb went off," 61-year-old resident Joe Ortega told the San Francisco Chronicle. "The trees go up like matches."

Cal Fire official Jonathan Cox said 80 houses have been destroyed between the two counties.

Santa Rosa fire chief Tony Gossner said it would take weeks to bring the flames under control, warning "it's going to be kind of long, and it's going to be painful."

The region is still reeling from devastating wildfires in 2017 when 44 people died and thousands of buildings were razed.

Smoke hangs among charred trees on the hillside behind a vineyard in Napa Valley, California

Further north the deadly Zogg Fire that killed at least three people has now ripped through 40,000 acres, again without containment.

Both fires were sparked Sunday by unknown sources, and spread rapidly through dry vegetation due to that have since eased. Temperatures remain high in the .

The new blazes come during a record season, with five of California's six biggest wildfires in history currently burning and 3.8 million acres scorched.

Climate change amplifies droughts which dry out regions, creating ideal conditions for wildfires to spread out-of-control and inflict unprecedented material and environmental damage.

Governor Gavin Newsom on Monday warned that California is only "now moving into the peak of the season," with Santa Ana winds sweeping south toward Los Angeles, where another major heat wave is expected.

Evacuations have been complicated by the coronavirus, which has hit the Golden State hard with more than 810,000 confirmed cases.