At least five people have died as dozens of wildfires sparked by lightning strikes continue to burn in Northern California.
The latest death of a resident in Solano County on Thursday followed that of a Pacific Gas & Electric utility worker assisting with advance clearing and a pilot on a water-carrying mission whose helicopter crashed on Wednesday.
Three civilians had died in Napa County since the fires began said Daniel Berlant, a Cal Fire assistant deputy director, adding that more than 30 civilians and firefighters have been injured.
Governor Gavin Newsom addressed the wildfires, calling them clear evidence of climate change, in a last-minute video recorded for the Democratic National Convention from a forest after he visited an evacuation centre.
He said: “If you are in denial about climate change, come to California.
“I confess this is not where I expected to be speaking here tonight.”
Mr Newsom had recorded an earlier, more lighthearted video, to be delivered at the convention but decided it did not strike the right tone amid his state’s disasters, said Dan Newman, one of his political advisers.
More than two dozen major fires were scorching California and taxing the state’s firefighting capacity, sparked by an unprecedented lightning siege that dropped nearly 11,000 strikes over several days.
The fires have destroyed 175 structures, including homes, and are threatening 50,000 more, said Mr Berlant.
Smoke and ash billowing from the fires has polluted the air throughout the scenic central coast and San Francisco.
Most of the activity is in Northern California, where fires have ripped through about 500 square miles of brushland, rural areas, canyon country and dense forest surrounding San Francisco.
More than 10,000 firefighters are on the front lines, but fire officials in charge of each of the major fire complexes say they are strapped for resources.
Some firefighters were working 72-hour shifts instead of the usual 24 hours and the state has requested 375 engines and crew from other states.
“That’s going to allow our firefighters that have have been on the front line since this weekend to have an opportunity to take some rest,” Mr Berlant said.