The National Meteorological Services (EMY) forecast a drop in temperatures of 7 degrees Celsius, accompanied by low visibility in regions and topical cloudy patches over the next two days. Weather conditions are expected to deteriorate due to the onset of what meteorologists dub the ‘Rex Blocking’ phenomenon. Crete and central Macedonia, as well as areas in the eastern mainland will see temporary rains and overcast weather. Meteorologists link the sudden weather downturn to the ‘Rex Blocking’ phenomenon, which rarely affects the eastern parts of the European continent. The phenomenon is caused when the flow of air masses in the atmosphere block the barometric systems from moving from west to east. This blocking was dubbed ‘Rex’ in honour of an American meteorologist who closely studies the phenomenon in 1950. Greece is usually affected by the ‘Omega Blocking’ systems, meteorologist Thodoris Kolydas told newspaper ‘Ethnos’. ‘The Rex system practically means that hot air masses from northwestern Europe will move southeastwards, while cold air masses will move from the Ukraine towards the Balkan peninsula’, he explained. The last time Greece had experienced such a phenomena was in 1991.