Milan, 29 April (LaPresse) – ‘During the day of 28 April, no unusual weather or atmospheric phenomena were detected, nor were there any sudden variations in temperature in our network of meteorological stations’. This is what the Spanish national meteorological service Aemet said in a note published on social media. Previously, the Portuguese energy company Ren (Rede Eletrica Nacional) had speculated that a rare atmospheric phenomenon known as ‘induced atmospheric vibration’ and characterised by ‘extreme temperature variations in inland Spain’ had caused the blackout that left Spain, Portugal and parts of southern France in the dark yesterday.