Greece is in the cross hairs as heat builds across the Mediterranean, with temperatures expected to climb toward a European record by the middle of next week.

Highs for the Greek mainland are forecast to reach 48C (118.4F) by Wednesday, testing the record of 48.8C set on the Italian island of Sicily two years ago. Some wildfires that started near Athens on Monday are still burning, as the country faces a new blast of Saharan heat over the next six days.

“The hard times are not over yet,” Prime Minister Kyriakos Mitsotakis said Thursday. The Greek premier is in contact with other European leaders to secure more jets and firemen to quell further flare-ups.

Interconnected domes of high pressure are bringing extreme heat across the Northern Hemisphere, from California’s Death Valley to Turpan in western China. Those heat waves are becoming more intense and prolonged as fossil fuel emissions warm the planet.

The Greek authorities have asked people with health issues to work from home on Friday and for public services to show flexibility in working hours. Government workers in outdoor activities have been told to stop providing services from midday.

The heat is raising demand for energy across southern Europe. Spain was forced to utilize all its gas plants to cope with surging electricity demand on Wednesday as people turned to air conditioning to cope, according to industry association Sedigas.

While the Mediterranean swelters, northern Europe will stay cool for the next 10 days. The temperature in London will be 5.5C below the norm on Saturday, according to Maxar Technologies Inc. Oslo will have a minimum of 9.5C on Friday.

Author: Eamon Akil Farhat, Sotiris Nikas and Ellie Harmsworth