The Greek Health Ministry is urging its citizens to stay indoors as temperatures begin to build toward what is forecast to be a torrid weekend across southern Europe.
Local reports suggest the Greek government is considering allowing civil servants to take Friday off due to an area of high-pressure, originating from the Sahara, which has been named Cerberus by meteorologists.
The heatwave sweeping Greece has been dubbed 'Kleon' as authorities ramp up measures to protect people.
Italy's meteorological authorities had called the heatwave 'Cerberus' - the name of the three-headed dog that guards the gates of the third circle of hell in Dante's Inferno.
Meteorologists in Europe are increasingly naming heatwaves - as they do with big storms and hurricanes- in order to draw attention to their dangers.
Authorities banned access to nature reserves and forests to reduce the risk of wildfires, while municipalities were opening air-conditioned areas in public buildings for people to shelter from the heat.
Greece's agriculture ministry also issued restrictions on the transportation and working hours of animals such as horses and donkeys offering rides in tourist areas during the heatwave.
Spain’s weather service said thermometers could potentially hit 45C in southeastern areas of the Iberian Peninsula, which are under alert for extreme heat.
That mark was reached Monday in the village of Loja near Granada.
While some relief is in store in the coming days for the Iberian Peninsula, other European countries will sweat through the weekend.
In Italy, 10 cities were put on high heat alert for older people and other vulnerable populations from Bolzano in the north extending southward to Bologna, Florence and Rome.
Temperatures are expected to reach 40 degrees in the Sardinian inland on Wednesday.
But storms in Italy's populous northern Lombardy region caused flooding, felled trees and ripped roofs off buildings.
More than 200 firefighters responded to emergencies in the regional capital of Milan, Varese, near the Malpensa airport, Lecco, near Lake Como, Sondrio, located in the Alps, and Bergamo.
New research this week has suggested that 61,000 people died from heat-related deaths as temperatures soared in Europe last summer.
The Mediterranean region is expected to record temperatures rising faster than many other areas of the globe because of climate change.
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