Cal Fire deputy chief Scott McLean described the wildfires as "extremely fast, extremely aggressive [and] extremely dangerous".
The Mendocino Complex of Fires east of Ukiah, California has blackened more than 273,664 acres, becoming the second largest wildfire in the state's recorded history. Fueled by low humidity, triple-digit temperatures and winds blowing across wide swaths of tinder-dry vegetation, the conflagration has expanded to three counties, surrounded an entire river and parts of neighboring reservoirs, and destroyed and damaged almost 170 homes and other structures.
The fires have spread rapidly in recent days to burn 283,800 acres of land - an area nearly the size of Los Angeles.
The other fire that makes up the "complex" is the River Fire west of Clear Lake.
Denham has spoken out to the Trump administration against what he sees as state efforts to "push more fresh water out to the ocean", Carlin said.
Trump's claims are false, according to California officials and wildfire experts.
The Ranch Fire is the larger of the two fires, having consumed more than 225,000 acres so far. But Nguyen said these have not happened in the affected areas.
Dozens of fires are now burning across California.
It is one of two major wildfires in California, the other one being the Carr fire, about 260km north of state capital Sacramento. Firefighters, with the help of 85 bulldozers, are building and reinforcing containment lines as the fire continues to burn.
The fire has destroyed dozens of homes and other buildings, and more than 11,000 structures remained threatened, the department said.
As of Monday, the Carr Fire had consumed 163,207 acres and was 45 percent contained. Think of California with plenty of Water - Nice! "Now they're doing three to four huge fires in a week".
Emily Carlin, spokeswoman for Rep. Jeff Denham, a California Republican and almond farmer who is one of the most vocal in the calls for more water for farms, said Monday she didn't know of her boss raising any argument about scanty water for firefighting.
Asked to comment about the president's tweets, Brown spokesman Evan Westrup was dismissive: "This does not merit a response". Jerry Brown had written in his request to Trump for a presidential major disaster declaration.
The Australian crews were first sent to Boise, Idaho, for training at the National Interagency Fire Centre; and joined USA and Canadian firefighters in the field on Tuesday.