Greece will see scattered afternoon storms in mountainous areas over the coming days before temperatures climb sharply toward the weekend, with highs potentially reaching 39°C, according to the National Meteorological Service (EMY).
Wednesday will bring generally sunny skies nationwide with light clouds, giving way to afternoon storms in mountainous parts of western and central Sterea Ellada, the Peloponnese, and possibly Crete.
Reduced visibility is expected overnight and early morning in western and southern regions, with fog likely to form over the Ionian islands, Cyclades and Dodecanese.
Temperatures Wednesday will range from 13-33°C in Western Macedonia to as high as 34-37°C in parts of the mainland, with highs of 35-36°C possible in the eastern Aegean islands. In Athens, expect sunshine with light southerly winds and temperatures between 24-35°C; Thessaloniki will see similar conditions, with highs up to 33°C.
Meteorologist Sakis Arnaoutoglou flagged a localized weather quirk expected in the Aegean on Wednesday: weakening winds combined with sea-surface conditions could trigger sea fog, particularly around the Cyclades, even as visibility elsewhere remains largely unaffected.
Mr. Arnaoutoglou said the bigger story going forward is the coming heat spike, with attention now turning to when the rise begins, which regions will be hit hardest, and how long the hot spell will last.
Temperature increases are expected to begin Friday and peak over the weekend, with highs potentially reaching 39°C in some areas as Greece heads into what forecasters describe as a "thermal anomaly" toward the end of August.