A wet winter in California eased much of the state's drought, but the resulting plant growth was expected to provide ample fuel for wildfires this summer.
California usually sees the worst wildfires of any U.S. state but states like Michigan, Vermont, New Hampshire and Maine are facing a higher risk at present.
"Approximately 6,000 homes collectively remained threatened at this time," Placer County Sheriff Lieutenant Josh Barnhart said on Wednesday.
Last week, the Mosquito Fire was just over 1,000 acres in size but has continued to grow over the past several days.
Heavy rainfall from tropical storm Kay has resulted in flash flooding in Death Valley so bad that roads have been damaged.
The blaze has been active for four days, burnt more than 40,000 acres, and is only 10 percent contained, according to local officials.
Nearly 230,000 acres had been burned across Oregon as of Friday.
There are warnings Tropical Storm Kay could blow more scorching air into southern California.
Squirrels around San Francisco have been spotted "splooting," leading residents to worry about their wellbeing.
More than 40,000 households are expected to lose power across Oregon on Friday.
The blaze, which killed two people on Tuesday, is threatening 2,000 structures.
"The Mosquito Fire exhibited extreme fire behavior yesterday and continued to burn overnight in the vicinity of Oxbow Reservoir," Cal Fire said.
Powerful wildfires are blazing in California, in Riverside County and the Tahoe National Forest.
Record temperatures have been recorded in California this week, leading to massive strain on the state's power grid.
As of Thursday, the Route Fire in Los Angeles County has grown to over 4,000 acres and is 0 percent contained.
A fire tornado has been created by a wildfire in Los Angeles County, with one observer calling it "the biggest one I've ever seen."
According to Cal Fire, the McKinney Fire has grown to 55,493 acres as of Tuesday and is currently 0 percent contained.
Evacuation orders remain in place as the McKinney Fire continues to burn out of control in Northern California.
Bold and significant climate action, anchored in meaningful clean energy expansion and fair environmental justice provisions, is the only way to secure the health, safety, and future of our families.
With California in the grip of a climate change-triggered drought, trees are so dry that they are entirely burning in the Oak wildfire.
The Oak Fire has become the largest wildfire of the year in California and continues to approach Yosemite National Park.
Firefighters continue battling the Oak Fire near Yosemite National Park on Monday.
The Oak Fire has been spreading rapidly and has been deemed the biggest fire in California since the start of 2022.
The blaze currently covers an area of over 3,500 acres, and is 22 percent contained by firefighters
"The Washburn Fire entered Yosemite's Mariposa Grove, one of our nation's most treasured giant sequoia groves," a conservationist said.
Temperatures have soared, with many states experiencing droughts so severe that scientists predict that wildfire season may soon last all year.
Lake Oroville, one of the largest reservoirs in California, is at 55 percent of its water capacity due to severe droughts.
Thousands of goats will eat through dry weeds in the area, that could go up in flames come the summer.