Firefighters in southwestern France kept a massive wildfire west of Bordeaux under control overnight on Wednesday, but authorities warned that soaring temperatures and strengthening winds could reignite the blaze later in the day.

Sophie Brocas, prefect of the Gironde department, said firefighters successfully contained several overnight flare-ups and maintained control of the fire.

“The night was quiet; the fire remains under control this morning, with several flare-ups quickly brought under control during the night,” Brocas said in a post on X.

The wildfire, burning in the Landes region west of Bordeaux, has consumed approximately 42,000 hectares (103,784 acres) of predominantly pine forest following weeks of exceptionally dry conditions fueled by successive heatwaves.

After battling the blaze for a week, French firefighters, assisted by crews from several European countries, have managed to contain its advance. However, officials warned that a fourth heatwave of the summer is expected to create more dangerous conditions.

According to France’s national weather service, Météo-France, temperatures in the region are forecast to reach as high as 42 degrees Celsius (108 degrees Fahrenheit) on Wednesday. Dry winds from the southwest in the morning and from the west later in the day are also expected to increase the risk of the fire spreading.

France is experiencing one of the most severe wildfire seasons in its history, with the total area burned already exceeding the record set in 2022.

The Landes region, known for its vast pine forests, is especially vulnerable during prolonged dry spells because the trees become highly combustible. The wildfire has already destroyed hundreds of homes.

Authorities have evacuated about 220,000 people, including residents and tourists, as the flames threatened the Cap Ferret peninsula on France’s Atlantic coast, which is accessible by only one road. Hundreds of evacuees were transported to safety aboard specially chartered ferries.

Elsewhere, several thousand residents south of the main fire zone were allowed to return home after firefighters contained a smaller blaze near the town of Biscarrosse.

As a precaution, several businesses on the outskirts of the historic city of Bordeaux temporarily suspended operations after the wildfire advanced to within approximately 15 kilometers (9 miles) of the metropolitan area.

Emergency officials remain on high alert as firefighters continue efforts to prevent the blaze from spreading under the forecast extreme heat and dry weather conditions.