Rapidly spreading wildfires in California, Nevada and Oregon have forced thousands of people to leave their homes, closed schools and businesses and caused widespread power outages across parts of the West Coast.

Nevada Governor Joe Lombardo, Oregon Governor Tina Kotek and California Governor Gavin Newsom have all declared states of emergency in their respective states. The proclamations allow the governments to obtain additional federal firefighting assistance.

The wildfires have been fueled in part by a late-summer heat wave that sent temperatures soaring into the triple digits and triggered air quality alerts for several areas in every state. While Wednesday brought cooler temperatures to Nevada, Oregon and Southern California, firefighters in Nevada expressed concern that Wednesday’s dry conditions and winds of up to 70 mph are expected to fuel rapid fire growth.

California

The Line Fire, a rapidly spreading wildfire in San Bernardino County that was only 14% contained as of Wednesday, has burned more than 34,000 acres, injured three firefighters and forced thousands of Southern California residents to evacuate since it broke out on Sept. 5.

Justin Wayne Halstenberg, a 34-year-old Riverside County resident, is suspected of starting the fire and was arrested Tuesday, the San Bernardino County Sheriff’s Office said.

The blaze is threatening more than 65,000 structures, Cal Fire reported Tuesday night, including homes and businesses in its path. Newsom also deployed the California National Guard to help contain the fire.

Fueled by high winds, the Bridge Fire has forced thousands of people to evacuate parts of Los Angeles and San Bernardino counties, including popular ski resorts Big Bear and Wrightwood, Cal Fire said. The wildfire erupted Tuesday night and grew to 4,000 acres in the Angeles National Forest by Sunday. By Wednesday, it had burned nearly 48,000 acres. The fire was 0% contained as of Wednesday.

The cause of the fire is under investigation.

On Monday, the Airport Fire broke out in the Santa Ana Mountains of Orange County before spreading into neighboring Riverside County. The blaze has burned more than 22,000 acres, injured 10 people, including eight firefighters, and is 0% contained.

Firefighters said mandatory evacuation orders were in place for both counties. Schools and businesses in the area were also closed due to smoke and ash polluting the air.

According to investigators with the Orange County Fire Authority, the fire at the airport was started by a spark from heavy equipment being used by workers in the mountains.

Nevada

Outside of Reno, about 20,000 people have escaped the Davis Fire since it broke out Saturday. The blaze has burned nearly 5,600 acres since it started in Davis Creek Regional Park. At the peak of the outages, about 17,000 people were without power, Nevada officials said.

NWS Reno called the fire an “exceptionally dangerous situation.” The weather service also noted that this was only the sixth time a “exceptionally dangerous situation” warning had been issued, and called the fire an “exceptionally rare event.”

More than 600 firefighters, including off-duty officers, have been called in to help fight the blaze. As of Wednesday, 31% of the fire is under control.

Oregon

Nearly 900 firefighters have battled the Rail Ridge Fire in Grant County. The blaze, believed to have been started by a lightning strike on Sept. 2, has burned more than 157,000 acres and is 12 percent contained.

Mandatory evacuations have been issued for several nearby counties and schools in the Dayville School District are closed for the week.

According to the Washington State Standard, the fire has destroyed seven homes and threatened approximately 730 homes, buildings and structures.

The Shoe Fly Fire has burned nearly 27,000 acres since it ignited during thunderstorms in Wheeler County in central Oregon on Sept. 2. About 65 homes are threatened by the blaze and several roads are closed.

However, firefighters have been optimistic in recent days about the progress they have made.

“We’ve put the fire behind us, we’re not trying to put it out and catch it anymore,” Incident Commander Joe Hessel told firefighters and landowners during a briefing Tuesday morning.

On Wednesday, the fire was 41% under control.