Smoke rises over a vineyard as the Glass Fire burns this week in Calistoga, Calif.
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Smoke rises over a vineyard as the Glass Fire burns this week in Calistoga, Calif. / AP

Updated at 4 p.m. ET

Firefighters are battling multiple fast-spreading wildfires in Northern California, including the heart of the state's wine country, as authorities say at least three civilians have been killed by the Zogg Fire in Shasta County.

At a Tuesday afternoon news conference, Daniel Berlant with the California Department of Forestry and Fire Protection, or Cal Fire, said that firefighters responded to 19 new wildfires throughout the state Monday.

Berlant also said that the August Complex Fire continues to be the largest in the state and that "it grew significantly yesterday to 938,000 acres" — almost 60,000 acres (more than 90 square miles) in a single day. Firefighters are struggling to contain the wind-driven blaze, he said.

Gusty winds on Monday helped two major fires — Zogg and Glass — to multiply in size. By Tuesday morning, California fire authorities said the winds had decreased overnight, raising hopes they would be able to make progress in containing the blazes.

The Zogg Fire in Shasta County and the Glass Fire, which has hit Napa and Sonoma counties, both started on Sunday. As of late Tuesday morning local time, both are 0% contained.

In Napa, authorities have imposed a mandatory evacuation order due to the Glass Fire for the city of Calistoga, which has a population of about 5,000. Some 60,000 residents in Napa and Sonoma counties are under evacuation orders or advisories, according to Reuters.

As of Tuesday afternoon, the Glass Fire has destroyed at least 94 structures, according to Cal Fire, in an area known for picturesque wineries and rolling hills. It has almost quadrupled in size since Monday, growing from about 11,000 acres to more than 42,000 on Tuesday.

The Zogg Fire in Shasta County, near California's northern border, has grown even faster. On Monday, it covered some 7,000 acres. On Tuesday, it covered more than 40,000 acres. Since Sunday, it has destroyed nearly 150 structures.

The causes of both the Glass and Zogg fires are under investigation, according to Cal Fire.

Since mid-August, 29 people have died in California as a result of the fires, including the three fatalities from the Zogg Fire.

Temperatures on Tuesday are 15 to 20 degrees cooler than the previous day along the Northern California coast, but the National Weather Service warns that inland areas will remain warm to hot through much of the week. The weather service has issued a red flag warning for parts of Southern California.

On Monday, California Gov. Gavin Newsom declared a state of emergency in Napa, Sonoma and Shasta counties due to the Glass and Zogg fires.

For the second time this wildfire season, the governor sent President Trump a letter requesting a presidential major disaster declaration to assist state and local wildfire response and recovery efforts. The first request was approved.

The governor said a "substantial" number of structures had been destroyed in these latest fires, including wineries.

So far, California has experienced more than 8,100 fires this season. Cal Fire reported that more than 3.8 million acres have burned.

"California has broken almost every record there is to break, and continues to see increased wildfire activity," Cal Fire said Tuesday.

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