Meteorologists are warning of an intense heatwave expected to hit Greece beginning Sunday, with temperatures projected to remain dangerously high through at least Thursday.
Greek weather expert Giannis Kallianos described the upcoming heatwave as one of the most severe of the summer so far. “This will be a difficult heatwave,” he said, adding that Athens could see temperatures climb to 41–42°C, while regions in eastern Central Greece, eastern Peloponnese, and Thessaly may experience highs of up to 44°C. In some cases, temperatures as extreme as 45°C are possible.
“Hopefully I’m wrong, and what I’m forecasting doesn’t come to pass,” Kallianos said, reflecting the growing concern among forecasters and authorities alike.
Rising Temperatures Across the Country
Meteorologist Klearchos Marousakis also warned of a sharp rise in temperatures starting Monday. In a public statement, he said that local temperatures could exceed 40°C in some areas, although it remains too early to determine the exact peak or duration of the hottest days. “We’re not yet in a position to identify the maximum values, but signs are not pointing toward extremes at this stage,” he noted.
He also highlighted the high fire risk, stressing that strong seasonal winds are expected to persist during the period.
Health Risks and Air Pollution
The heatwave is expected to significantly worsen air quality, with experts warning about the health risks posed by the combination of high temperatures, air pollution, and elevated ozone levels.
“This triple combination is extremely harmful, especially for vulnerable groups such as people with respiratory or cardiovascular conditions,” said Dimosthenis Sarigiannis, professor of environmental engineering.
Factors influencing the health impact include vegetation density, vehicle traffic, industrial activity, and prevailing weather conditions such as humidity and lack of wind.
Authorities are urging the public to take protective measures, especially at night when temperatures may remain uncomfortably high. Extended periods of heat with no overnight relief can pose serious health risks. Elderly individuals, outdoor workers, children, pregnant women, and people with chronic illnesses are particularly vulnerable.
Forecast Through the Weekend
Thursday, July 17:
Temperatures are expected to reach 38°C or higher in some regions. Nighttime temperatures will remain elevated, contributing to increased thermal stress. Strong heat warnings are in place across much of Macedonia, Thrace, Central Greece, the Peloponnese, Crete, and the North Aegean. In Thessaly and parts of Eastern Central Greece, the risk is considered very high.
Friday:
Northern regions may experience clouds and isolated storms, particularly in eastern Macedonia and Thrace. Elsewhere, the weather will remain mostly clear, with occasional afternoon clouds and isolated showers in mountainous areas. Temperatures will drop slightly in the north but remain between 34–37°C in central and southern regions.
Saturday and Sunday:
Mostly clear weather is expected, with occasional clouds and local showers in eastern mainland Greece during the afternoon. Winds will range from 3 to 6 on the Beaufort scale, mainly from northern directions. Temperatures will remain steady on Saturday, with a slight increase expected Sunday.
Heat Alerts and Fire Risk
Forecast models from the National Observatory of Athens (meteo.gr) and the HEAT-ALARM system indicate significant heat stress for much of the country. Citizens are strongly advised to stay hydrated, avoid prolonged sun exposure, and cool off regularly. Public health officials also stress the importance of checking in on vulnerable individuals and following official guidance.
