Friday, August 21, 2026, marks the first day of an extended heatwave forecast across Greece — one expected to last approximately one week. According to the Hellenic National Meteorological Service (EMY), temperatures will climb to 36–38°C today across much of the mainland, with the most intense phase anticipated between Saturday, August 23, and Tuesday, August 26. During this period, several inland regions — particularly in Thessaly, Central Macedonia, and parts of Epirus — may see mercury levels reach or even exceed 40°C.
A Late-Summer Surge
Despite being near the tail end of summer, Greece is set for a prolonged stretch of unusually high temperatures — up to 7°C above seasonal norms. While coastal and island areas will experience relatively milder conditions — ranging from 29°C in the Cyclades to 36°C in the Dodecanese and eastern Aegean — inland zones face significantly more extreme heat. For instance, central Macedonia could see local highs of 37–38°C, while western mainland mountainous areas may register isolated afternoon thunderstorms amid otherwise clear skies.
Regional Breakdown
In northern Greece — including Macedonia and Thrace — skies will remain mostly clear, though brief cloud buildup is possible over western mountain ranges in the afternoon, bringing isolated showers or thunderstorms. Winds will be light to moderate, generally from northerly directions, reaching up to 5 on the Beaufort scale locally.
Across the Ionian Islands, Epirus, western Sterea Ellada, and western Peloponnese, conditions will also be predominantly sunny, with occasional afternoon cloud development over higher elevations. Northerly winds will gradually shift to northwesterly by midday, strengthening slightly in places.
In Thessaly, eastern Sterea Ellada, Evia, and the eastern Peloponnese, skies will stay largely clear, with only passing clouds over mountainous terrain during peak heating hours. Winds will remain variable but generally light.
Health and Safety Considerations
Rising humidity levels are expected to amplify the perceived heat, increasing thermal stress on the human body. Authorities urge heightened vigilance — especially for vulnerable groups such as the elderly, young children, and those with pre-existing health conditions. Staying hydrated, avoiding prolonged sun exposure, and limiting outdoor activity during peak afternoon hours are strongly recommended.
This sustained hot spell underscores the growing frequency of extreme weather events in late summer — a trend increasingly observed in recent years across southern Europe.