According to the California Department of Forestry and Fire Protection (Cal Fire), the blaze ignited on Wednesday night exploded very fast, scorching over 40.5 sq.km by Thursday noon with zero containment, reports Xinhua news agency.
More than 500 firefighters were battling the blaze in Sonoma County, but their overnight efforts could only focus on evacuations and the high winds made the fire difficult to contain.
"Our aircraft can't drop in those conditions. When you have that kind of wind speed, the resistance to control is beyond our capabilities. Because of the terrain and fuel conditions and the heat and humidity, the containment is still very challenging." Mark Parks with Cal Fire told local KCRA news channel.
There were reports that dozens of buildings were burned down but so far there is no report of casualties.
The fire was reported to have started near the Geysers Geothermal Plant, the world's largest geothermal field, but there officials were yet to ascertain it.
Meanwhile, another wildfire dubbed the 'Tick Fire' was reported on Thursday in the Southern California city of Santa Clarita, 60 km northwest of downtown Los Angeles, which moved quickly downhill toward Canyon Country, a residential community nearby.
The flames had spread to 0.8 sq.km within 20 minutes and scorched over 3.4 sq.km by Thursday evening.
Aerial video showed that some outdoor structures were damaged and the flames were dangerously close to homes in some areas. At least one home appeared to be on fire.
Hundreds of firefighter from Los Angeles County and Orange County were battling the blaze with four airtankers.
The fire came amid red flag warnings issued for some areas in Southern California due to extreme wildfire risk.
( With inputs from IANS )