Greece is set to experience its first major heatwave of the summer, with temperatures forecast to soar as high as 42°C in parts of the country between Sunday and Tuesday, prompting warnings about dangerous conditions in urban areas.
According to meteorologist Giorgos Tsatrafyllias, the hottest conditions are expected from July 19 to July 21, with Thessaly, Phthiotis, Aetolia-Acarnania, Boeotia and Central Macedonia likely to record highs of 41–42°C.
In Attica, temperatures are expected to exceed 38°C on Sunday before climbing to around 40°C on Monday and Tuesday. Forecasters expect a noticeable drop in temperatures after the heatwave passes.
Temperatures already on the rise
The Hellenic National Meteorological Service (EMY) said Saturday will bring mostly sunny conditions, with some afternoon cloud over mainland Greece and isolated showers or thunderstorms in the mountains of Macedonia.
Temperatures are forecast to reach:
- 32°C in the Cyclades
- 34–36°C across most islands
- 37–38°C over mainland Greece
- Up to 39°C in some inland regions
North winds of 3–5 Beaufort are expected, strengthening to 6–7 Beaufort in parts of the Aegean before easing later in the day.
Why cities feel even hotter
Weather experts from Meteo.gr and the National Observatory of Athens warn that cities will experience even more oppressive conditions due to the urban heat island effect.
Concrete, asphalt, dense buildings and limited vegetation absorb and store heat throughout the day before releasing it slowly overnight. This keeps temperatures significantly higher in urban areas than in surrounding rural regions, especially after sunset, reducing the body’s ability to recover from prolonged heat exposure.
Heat generated by traffic, air conditioning systems and other human activity further intensifies temperatures in city centres.
The prolonged heat poses the greatest risk to:
- Older adults
- Young children
- People with chronic health conditions
- Outdoor workers
- Those without access to air-conditioned or cool indoor spaces
How cities can reduce extreme heat
Experts say tackling urban heat requires a combination of long-term planning and infrastructure improvements.
Expanding green spaces, planting more trees, creating shaded public areas and cooling centres, protecting open spaces that improve airflow, and adding water features can all help lower urban temperatures.
They also recommend using reflective or light-coloured materials on roofs, roads and buildings to reduce heat absorption.
Meteo.gr stressed that every city faces different challenges, meaning heat mitigation strategies should be tailored to local conditions and prioritise communities most vulnerable to extreme temperatures.
The awareness campaign includes educational graphics produced by the United Nations Office for Disaster Risk Reduction (UNDRR) and translated into Greek through a collaboration with Meteo.gr and the National Observatory of Athens.