The fires had stretched Sonoma and Napa counties firefighting resources to the breaking point.
The declaration authorizes the mobilization of the California National Guard to the wine country, north of San Francisco. Brown said the fires threaten infrastructure, people and their homes.
Buildings in California's Napa and Sonoma counties were being evacuated early on Monday morning after multiple, fast-spreading wildfires engulfed the area with thick smoke and large flames, according to fire officials and local media.
The remains of a auto sits near the Fountaingrove Inn as it burns at rear in Santa Rosa, Calif., Monday, Oct. 9, 2017.
Residents told of terrifying pre-dawn scrambles to flee the raging flames.
"We've seen major devastation of several neighborhoods of Santa Rosa, both residential and commercial", Chris Coursey, Santa Rosa mayor told the Sacramento Bee. "It's a scary time".
"Fire has burned all the way through the Silverado Country Club area", Biermann said in a reference to the Silverado Resort and Spa.
According to CalFire, a 200-acre fire near Atlas Peak in the hills above Napa led to the evacuation of hundreds of homes. The Atlas Peak fire near the city of Napa had burned more than 10,000 acres by 6 am.
Fourteen large-scale fires are now burning in the region, and Cal Fire has noted that the estimates with regards to the destruction are likely conservative. The boss said firefighters are now concentrating their endeavors on sparing lives as opposed to attempting to stop the bursts.
Napa officials said three evacuation centers had been opened - at the Crosswalk Community Church on First Street and at the Napa County Fairgrounds.
Several wind-driven fires are burning out of control in the region, and California governor Jerry Brown has declared a state of emergency for Napa, Sonoma and Yuba counties. The smaller Nuns Fire, in Sonoma, was at 5,000 acres by about midday, officials said.
The area of Fountaingrove was particularly hard-hit, with photos showing numerous homes on fire. The area was under a mandatory evacuation. Certainly with day just breaking now, we are starting to see the structures that are affected", she said shortly after sunrise."The gusts are very, very - they're tremendous and it's what makes this fire unpredictable. The San Mateo County Sheriff's Department issued a notice to residents to expect a strong smell of smoke from the fires. "Keep pets inside for protection".
The cause of the fires is still under investigation.