Massive power outage in Spain, Portugal and parts of France, what could be possible reason?

Millions of people in Spain and Portugal were left without electricity on Monday due to a nationwide power outage.

The blackout was also reported to have affected residents of Andorra and portions of France that border Spain

Power went out across all of Spain and Portugal cutting cellphone and internet networks, halting trains, buses and trapping people in elevators

Portugal’s REN said a “rare atmospheric phenomenon” had caused a severe imbalance in temperatures that led to the widespread shutdowns.

REN said: “Due to extreme temperature variations in the interior of Spain, there were anomalous oscillations in the very high voltage lines (400 kV), a phenomenon known as ‘induced atmospheric vibration’.

Another potential reason is a fire on the Alaric mountain in southwest France that destroyed a high-voltage power cable between Perpignan and eastern Narbonne.