Greece enters a fully autumnal weather pattern starting Tuesday, September 22, as a sharp change in weather brings heavy rain and thunderstorms, frequent lightning, possible hail, and a significant temperature drop of up to 6 to 7 degrees Celsius.
The weather deterioration begins in the early morning hours, with the most intense conditions centered over the broader northwestern Aegean region. Magnesia, the Sporades, Halkidiki, and central and northern Evia are in the eye of the storm, while the Hellenic National Meteorological Service (EMY) has issued an Emergency Weather Deterioration Bulletin, warning of locally heavy rain and thunderstorms.
Greece weather: “We’re entering an autumn week”
As meteorologist Christina Rigou explains to parapolitika.gr, the weather shift will be felt immediately. “The weather is indeed changing. We are entering an autumn week, kicking off with a spell of bad weather. We expect rain and thunderstorms, which will be severe in parts of the country. We will also see some localized hail and intense lightning activity, which will be concentrated mainly over sea areas,” she notes.
The weather phenomena begin early across northern Greece, primarily affecting Halkidiki, while unsettled conditions will also hit the islands of the northern Aegean, the Sporades, Evia — mainly in its central and northern sections — as well as eastern Thessaly, with the epicenter in Magnesia.
In the Sporades, Evia, and the northwestern Aegean, the unsettled weather is expected to persist through the afternoon.
Where the greatest caution is needed
Rain is expected throughout the day in several other parts of the country as well, though with lesser intensity, while brief thunderstorms may develop mainly over mountainous areas.
“The areas most affected by the storm system will be Halkidiki, eastern Thessaly, Evia, the Sporades, and the northwestern Aegean,” Ms. Rigou emphasizes. Special caution is required in areas where the strongest thunderstorms are expected to develop, as the meteorologist warns that localized problems — and even flash flooding — cannot be ruled out.
Emergency weather bulletin issued by the Hellenic National Meteorological Service
According to the EMY’s emergency bulletin, heavy rain and thunderstorms are forecast in Magnesia — particularly in coastal and maritime areas — from the early hours of the day. In the Sporades and Halkidiki, the intense weather phenomena will last from the early hours through the afternoon, while in central and northern Evia they are expected from morning until afternoon.
In Magnesia, the weather phenomena are forecast to persist until the early morning hours of Wednesday, when they are expected to weaken significantly.
Temperature “plunge” of up to 7°C
According to Ms. Rigou’s forecast, the change is not just about rainfall. The thermometer is set for a noticeable plunge, effectively marking the first truly autumnal week of the season.
In Macedonia and Thessaly, temperatures are not expected to exceed 24 to 26°C today, compared to Monday’s locally recorded highs of 32°C. Temperatures in the 30s will only persist further south, mainly in the Peloponnese and Crete.
From Wednesday, September 23 through the end of the week, however, the temperature picture will be firmly autumnal across most of the country, with maximum values generally hovering around 24 to 26°C.
Northerly winds will reach up to force 6 on the Beaufort scale, though based on current data, they are not expected to cause any significant problems.
Rain in Athens too — thermometer at 26°C
A change in conditions is also expected in Attica. From the early hours of Tuesday, localized rain showers are possible, initially without significant intensity. Towards midday, however, brief thunderstorms are forecast over northeastern Attica, while the temperature drop will also be particularly noticeable.
The thermometer in Athens is expected to reach around 26°C, down from Monday’s 32°C, recording a drop of approximately 6 degrees within a single 24-hour period.
Tuesday thus marks the effective start of the autumn transition, with the most intense weather phenomena gradually easing from Wednesday morning onwards — though the cooler temperatures are here to stay through the end of the week.
