US media reported more than 1,500 buildings have been ravaged by flames so far as more than a dozen ferocious blazes spread across Napa, Sonoma and Yuba counties.
Terrified residents told how they escaped their burning homes in the middle of the night amid scenes of "Armageddon".
Schools were closed across the worst-affected areas.
Reports on Twitter claim California Highway Patrol helicopters have been dispatched to rescue 25 workers trapped at the Stags' Leap Winery in Napa.
ABC News reports 20,000 people have been ordered to leave their homes with hospitals also evacuated.
Surrounding counties have been placed on alert amid fears the fire could spread.
The fires broke out on Sunday night and dramatically tore through communities today after being whipped up by powerful winds.
Billowing smoke has been reported near major Californian cities San Francisco, Oakland and San Jose.
Hundreds of firefighters have been scrambled to rescue missions but so far there have been no reports of injuries or fatalities.
Fire chiefs said the severity of the blaze was proving problematic for crews.
Napa County Fire Chief Barry Biermann told a press conference: "Right now with these conditions we can't get ahead of this fire and do anything about the forward progress."
The California Fire Service said fires have swept across more than 30,000 acres of land with evacuation centres set up at schools and town halls.
US media have reported more than 50,000 acres of land has been engulfed by flames.
Authorities in neighbouring Marin County said they had received an "overwhelming" number of 911 calls as smoke was pushed into the region.
Witnesses described apocalyptic scenes as pictures and video shared on social media captured the carnage.
Santa Rosa resident Ron Dodds told KTVU: "It's a scary time. It looks like armageddon."
Emilia D'Anzica tweeted "My family & I escaped this fire in the middle of the night - many homes & vineyards blazing. Hoping everyone is out alive."
Forecasters said strong winds are expected to cease by midday Monday (8pm UK time) but warnings will remain in place while the weather is hot and dry, CNN reported.