'Like the apocalypse': France's worst wildfires spawn rare pyrocumulonimbus cloud

Wildfires raging across southwestern France have forced more than 220,000 people to evacuate in the Gironde department alone, where a pyrocumulonimbus cloud — a rare, fire-generated storm cloud — was observed for the first time in French history.

The fire broke out July 22 in Saumos in the Gironde department and entered its fifth day Sunday, having scorched 42,000 hectares (420 square kilometers) in Gironde alone, according to AFP and other international media. That is roughly seven times the area of Manhattan and about four times the size of Paris.

French Interior Minister Laurent Nunez told TF1 he had "never seen a convective wildfire of this scale," adding that about 50 firefighters had been injured. Prime Minister Sébastien Lecornu wrote on X that the fires engulfing the country had reached "an unprecedented level."

The blaze is spreading southeast toward Bordeaux, France's premier wine-producing region. Bordeaux Mayor Thomas Cazenave said Sunday the fire had advanced to within just 15 kilometers of the city limits.

More than 220,000 people have been evacuated across the Gironde area so far, and authorities have issued an additional evacuation order covering 55,000 residents near Bordeaux.

Tourists who fled overnight from the Cap Ferret peninsula — an upscale resort about 60 to 70 kilometers west of Bordeaux — described flames shooting up to 35 meters high and thick black smoke filling the sky.

Journalist Dominique Chapat told RTL radio: "The sky was pitch black and ash was falling like rain. It was like a scene from the apocalypse."

Authorities have deployed 2,500 firefighters and 2,700 military and police personnel in Gironde alone, but containment remains elusive. Repeated heat waves this summer have left vegetation extremely dry, and strong winds are driving an uncontrollable spread.

A spokesperson for the French National Federation of Firefighters told AFP: "We don't know how the fire will spread. The flames are constantly moving. It's like David versus Goliath."

French fire authorities said the blaze had generated a pyrocumulonimbus cloud — a mushroom-shaped formation produced by the intense heat of large wildfires or volcanic eruptions.

The phenomenon forms when enormous ground-level flames and thermal energy rapidly push air upward. The resulting cloud generates its own winds and lightning, which can trigger even larger fires.

Marc Vermeulen, head of the Gironde fire and rescue service, said he witnessed a pyrocumulus cloud develop into a pyrocumulonimbus at around 6:20 p.m. Saturday. "This is a phenomenon that has never been observed in France," he said.

President Emmanuel Macron convened an emergency cabinet meeting Monday to discuss the wildfire crisis.

France's national weather service warned that a new heat wave is forecast to begin Wednesday, with temperatures in some areas expected to reach 40 degrees Celsius, raising fears that the fire danger will intensify further.