Hundreds of people have been evacuated and a major incident declared after a wildfire spread over more than 80 hectares (200 acres) on the coast of Suffolk, just a few miles from the Sizewell B nuclear power station.

The fire – described by one witness as “apocalyptic” – was still not completely under control as of late Thursday afternoon, according to Jon Lacey, the chief fire officer at Suffolk fire and rescue.

He said: “The wind change has helped a little bit, unexpectedly, and also a helicopter [dropping water] is helping to dampen the fire down. Whether it’s actually under control, I wouldn’t commit myself to that just yet, but we are surrounded by resources to protect property and life.”

The wildfire came a day after half of England was declared to be officially in drought, including East Anglia and six other areas. On Thursday, Natural Resources Wales declared a drought across the whole of Wales, which is on course for its driest July since records began nearly 200 years ago.

As the climate crisis supercharges “whiplash” wet-then-dry weather, the UK and Europe are seeing back-to-back heatwaves that encourage vegetation to grow but then dry it out, producing ideal fuel for fires.

Firefighters have responded to 393 wildfires across England and Wales in July, making it the busiest month on record and placing significant pressure on crews and resources.

Phil Garrigan, the chair of the National Fire Chiefs Council, said: “Wildfires are no longer isolated or seasonal events. They are becoming a recurring and growing feature of the risks facing our communities and emergency services.

“As climate and environmental conditions continue to change, we must ensure our fire and rescue services are equipped to meet that challenge.”

In France, the fires around Bordeaux continued to smoulder on Thursday, while Spain and now Turkey are dealing with major blazes.

In Suffolk, crews were called to reports of a fire at Dunwich Heath, near Leiston, shortly after 5.30pm on Wednesday and that night a number of homes were evacuated.

Rob Tucker, who has a cottage at Cliff House holiday park, said: “We were evacuated at 10pm. One of the guys that works at the holiday park came along and said we were being evacuated. Everything’s been left behind apart from my cars and the clothes that we were wearing.”

A nearby caravan park was also evacuated on Thursday and residents opened up their homes to help. Andrew Turner, the chair of Westleton parish council, said: “I had two families in my house. Two families and two dogs. There are now pillows and stuff in the village hall but the objective is to get everyone into houses. The council is still taking names of people who are willing to put up rooms.

“We’re a tightknit community, it’s great to see the community come together, I wouldn’t expect anything less.”

The damage to wildlife is expected to be considerable because the fire hit the RSPB’s Minsmere nature reserve.

The charity’s area manager, Adam Rowlands, said: “The heathland habitat where the main fire is is home to really special and rare species in the UK, birds like nightjars, nightingales and Dartford warblers.

“It’s absolutely devastating to see this damage compared to last night when the fire started, I saw a 20ft fireball burning through the trees, with nightjars flying away from the fireball. Last night I stood on the heath and it was apocalyptic, the sky was orange, the smoke was billowing, it could be seen and smelled 20 miles to the north.”

Firefighters say there is not thought to be any danger to Sizewell B, which is a few miles from the blaze. A spokesperson for EDF, which operates the site, said the wildfire was not affecting operations and was being closely monitored. It is understood Sizewell B has an emergency plan that covers a range of scenarios including a fire on site.

Freddie Gulliver, from the Suffolk Joint Emergency Planning Unit, said there was currently no concern that the fire might spread towards Sizewell B. “Sizewell is not a risk, a concern, currently at this stage,” he said. “From the meetings we’ve had at the moment, that hasn’t been a concern.”

People have been urged to avoid the area where possible and keep windows and doors closed.

Andy Burnham promised support to firefighters on Thursday. Speaking to reporters during a visit to Cumbria, the prime minister said: “We’ve got the situation under close monitoring, and I’m receiving regular updates. It is a very serious incident.”

Dr Zakary Campbell-Lochrie, a lecturer in fire science at the University of Edinburgh, said: “This wildfire is occurring at the same time as drought conditions have officially been declared in large parts of England, including Suffolk.

“The hot, dry weather conditions, including the multiple heatwave events across much of the UK in recent weeks, lead to strong drying conditions for vegetation, which can subsequently be highly susceptible to ignition and can present a much greater danger when fires do occur.”

The climate crisis, driven by the burning of fossil fuels, is making heatwaves more intense and more frequent. A fortnight ago, the Reform-led Suffolk county council voted to rescind a climate emergency declaration that had been adopted in 2019 and removed references to the climate emergency from council policies, strategies and communications “where appropriate”.

On Thursday, the UK Health Security Agency said England was on track to record its highest ever number of heat-related deaths this summer.