NAVALUENGA (AFP) — Firefighters in France and Spain raced Tuesday to contain massive wildfires before another heat wave forecast to bring hotter temperatures and drier conditions across Western Europe.

The largest blaze, near the French city of Bordeaux, remained under control overnight after firefighters contained several flare-ups. The wildfire has burned about 42,000 hectares (103,000 acres), forced 220,000 people to evacuate and destroyed 240 homes over the past six days.

“Mobilization is still full and complete, particularly on the eve of a day that is expected to be marked by a significant rise in temperatures and a drop in humidity,” the prefect of France’s Gironde region said, describing conditions as “highly unpredictable.”

French President Emmanuel Macron, who visited a crisis center Monday, warned that “The coming weeks will be tough and we have to hold out.”

A separate wildfire in neighboring Landes was contained after burning about 500 hectares (1,235 acres) and forcing more than 30,000 people to evacuate. About 15,000 residents were allowed to return home Monday evening.

In Spain, where fires continue to burn west of Madrid, about 60,000 people remain displaced.