A strong wildfire that broke out in northern California on Tuesday is threatening thousands of houses, as the state is experiencing an intense heatwave that could be historic – forcing about 28,000 residents to flee their homes. 

The Thompson fire rapidly spread over more than 3,500 acres (1,416 hectares) close to the city of Oroville, an hour outside of the Californian capital of Sacramento.

The cause of the fire remains under investigation. 

Photographers witnessing the wildfire in the isolated community of Butte County photographed dramatic scenes as it tore through houses and cars. At least four buildings have been destroyed, as per authorities. 

The state's fire brigade, which had 0% containment on Wednesday afternoon, dispatched around 1,400 firefighters and at least half of the eight verified injuries were firefighters, as the high temperatures continue to endanger them.

CalFire's public relations officer, Ed Fletcher, stated that although the organization makes an effort to guarantee firefighters receive relief and rest, the already difficult labor is exacerbated in severe weather.

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“The combination of events has presented a huge challenge for firefighters,” he said, as he called on the public to take extra precautions.

“It’s a tough thing to do,” he added. “You are asking people to hike up a mountain when it’s 108F outside.”

On Wednesday, California Governor Gavin Newsom issued a state of emergency to guarantee that resources are ready and accessible to assist with the fire's response and recovery.

In response to the Thompson Fire, we have proclaimed a state of emergency in Butte County.

California is using every available tool to tackle this fire & will continue to support impacted communities.

For real-time information on active fires, visit https://t.co/jBK8AuvDkt. pic.twitter.com/SroIhbnwbN

— California Governor (@CAgovernor) July 3, 2024

Newsom noted that California has received a fire management assistance grant (FMAG) from the Federal Emergency Management Agency (FEMA) to cover the costs and damages of the wildfire.

The Fourth of July brings with it a higher risk of fire because of the combination of hot, dry weather and celebratory fireworks as they can cause an average of over 18,500 fires to start.

Over a dozen fires have broken out since Monday, and this week is expected to have extremely high levels of fire activity and behavior, making it challenging to limit fresh blazes.

Cal Fire deputy director Nick Schuler stated, “It’s going to be a challenge both day and night – so the message is prevention," and the agency is at peak staffing levels to prepare for what is expected to be an extremely busy week, extending into an extremely busy summer.

Parts of the state are expected to experience "extreme" heat risk starting on Wednesday, which is the highest category listed on the National Weather Service's index, and authorities warned that the harsh weather could persist until Sunday or longer. Life-threatening triple-digit temperatures may persist for more than a week in certain areas.

The state capital of California, Sacramento, was expected to see temperatures between 105F and 115F (40.5C and 46.1C) on Sunday.

This was from midday Tuesday, but this video from the Fire Integrated Real Time Intelligence System (FIRIS) Intel 12 aircraft gives a good overview of the #TollFire north of Calistoga. pic.twitter.com/XuvtyLyteV

— CAL FIRE LNU (@CALFIRELNU) July 3, 2024

During a broadcast discussion of the heat event on Monday, climate scientist Dr Daniel Swain relayed, “This is going to be a severe, prolonged, potentially record-breaking heatwave that may have large impacts for much of California.”

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He reiterated that the long duration will only add to the potential impacts and intensity, especially because little relief can be expected even after the sun sets.

“It just isn’t going to cool off – even at night,” Swain said.

Around this time last year, a wildfire that erupted in Northern California as well forced the evacuation of 500 homes and other structures.