As Greece enjoys its early summer rhythm, the Hellenic National Meteorological Service (HNMS) has issued an emergency weather warning for a swift and notable change in conditions over the next 48 hours. Starting Friday, June 20, the weather is expected to deteriorate sharply in parts of northern Greece, with the unstable front pushing south by Saturday, June 21 — just as the country prepares to celebrate World Music Day.

Friday Forecast: Storms Building in the North

While the day will begin mostly sunny and warm across the country, conditions will shift dramatically from midday onwards in northern regions.

According to the HNMS bulletin, strong thunderstorms are forecast to hit Macedonia, Thrace, Thessaly, Epirus, and mountainous areas of Central Greece and the Peloponnese.
These storms are expected to be accompanied by short bursts of powerful winds known locally as bourinia.

  • Winds: Western to northwesterly winds at 3–5 Beaufort, reaching up to 6 in the southeastern Aegean.
  • Temperatures: No major changes expected on Friday. Highs will reach 35–36°C on the mainland, 31–33°C on the islands, and up to 35°C in southern Crete and the eastern Aegean.

Saturday Forecast: More Widespread Instability

The weather phenomena will intensify on Saturday, June 21, affecting more central and southern parts of the country. Strong thunderstorms and heavy rain are expected in:

  • Central Macedonia (notably Halkidiki)
  • Sporades Islands
  • Eastern Thessaly and Evia
  • Central Greece and the Peloponnese (especially from late morning)
  • Epirus (mainly in the afternoon)

Elsewhere, including Athens and Crete, the weather will remain mostly clear, though isolated showers may develop in mountainous areas during the afternoon.

  • Visibility: Early morning fog may reduce visibility in western regions.
  • Winds: Northern winds will strengthen to 6–7 Beaufort in the Aegean.
  • Temperatures: A notable drop of 3 to 5 degrees Celsius is expected, with highs peaking at 30–32°C.

While this sudden change is not uncommon for early summer, the intensity of local storms, particularly in Macedonia, Central Greece, and parts of the Peloponnese, may cause disruptions. Travelers, event organizers, and residents are advised to monitor forecasts and updates from EMΥ and local authorities.