Paris is facing one of its worst heat waves in more than a century, with daily average temperatures hovering around 30 degrees Celsius (86 degrees Fahrenheit) over a seven-day period and hitting a maximum of 39 degrees on Sunday, according to forecaster Meteo-France. The hot weather will last through the middle of next week, creating the worst heat wave conditions in the French capital since the 2003 scorcher that lasted 10 days, Meteo-France meteorologist Francois Jobard said in a tweet on Friday.

The Paris region’s prefect, the chief administrative official, on Thursday, declared a heat-wave alert, activating measures such as delivering fans to vulnerable people and handing out water bottles to the homeless. After the 2003 heatwave killed an estimated 15,000 people in France, the country introduced a “plan canicule” to limit the impact of episodes of hot weather.

Heat waves in France have become more frequent and more intense in the past 30 years, and climate change means their number and duration is expected to increase further in the 21st century, according to Meteo-France. The country is already experiencing unusually warm weather, registering its 14th consecutive month of above-normal temperatures in July and the warmest January-July period since 1900.