Firefighters in Spain, Portugal and Greece battled ongoing wildfires Friday, an important religious holiday in all three countries, as persistent hot, dry conditions challenged efforts to contain the blazes.

A heatwave with temperatures exceeding 40 degrees Celsius, or 104 Fahrenheit, on several days this month was expected to last through Monday.

ATHENS, Greece (AP) — Fire crews in Greece, Spain and Portugal raced Thursday to contain wildfires, taking advantage of calmer winds that slowed the blazes’ advance. Much of southern Europe, however, remains at high risk under hot, dry conditions.