Severe storms lash Greece with hail, floods and over 31,000 lightning strikes

Storms sweep mainland Greece

Heavy rain and violent thunderstorms struck much of the Greek mainland on Friday, with the National Observatory of Athens reporting intense electrical activity. According to the METEO unit, the highest rainfall total by 19:20 local time was 63 mm at Narthaki in Larissa, followed by Neos Palamas (Fthiotida) with 61 mm, Farsala with 51.6 mm, Polygyros with 46.8 mm and Palaiokoundoura (Mandra, Attica) with 39.6 mm.

The Meteosat-12 satellite’s Lightning Imager recorded 31,155 electrical discharges over Greece between midnight and 19:00 local time, encompassing cloud-to-ground strokes, intra-cloud flashes and discharges into the surrounding air.

Flooding and damage

In Attica, the storm transformed roads into torrents. Acharnes saw central thoroughfares submerged, particularly Stratigou Kaliari Street leading to Ano Liosia, where accumulated water turned the road into a river and made vehicle passage dangerous. Civil Protection teams from the municipality and the Fire Service blocked the route, advising drivers arriving from the Parnitha area to turn back.

Ano Liosia also experienced a heavy hailstorm, with several streets becoming small rivers. Officials reported that hail covered part of the road surface and that a fallen tree branch blocked the carriageway. Heavy vehicles managed to negotiate some stretches, but the authorities continued to warn that areas with large volumes of water remained hazardous.

Further north, Thiva suffered a rapid, violent hailstorm around midday. Hail, torrential rain and numerous lightning strikes blanketed roads and other surfaces within a short space of time, as documented by Lamia Report. The same fast-moving system brought rain and hail to parts of Larissa (especially the Elassona area) and to Kastoria, where images showed significant accumulations.

Scientific perspective

Kostas Lagouvardos, research director of the National Observatory of Athens and head of the METEO unit, described the day’s instability as entirely normal for the season.

May and June are the period of intense instability and thunderstorm activity in Greece.

He confirmed that very strong lightning activity had been recorded and that rain had also fallen in parts of Attica.

Forecast

The EMY’s updated severe weather bulletin on Friday afternoon added Thrace and the northeastern Aegean to the areas expected to see intense phenomena. Rain is forecast to continue on Saturday, but according to Lagouvardos temperatures will begin climbing again from Sunday and Monday to levels slightly above normal. Based on data available to date, temperatures are likely to remain near the seasonal average until 20 June, with no immediate sign of a heatwave.

Rains will continue on Saturday, but from Sunday onwards temperatures will rise again to levels slightly above normal. From the data we have, temperatures will stay near normal levels until 20 June. There is no sign of an imminent heatwave.