Various meteorologists have confirmed that the enormous bang that was heard on Sunday evening in a large part of the province of Groningen was caused by a thunderstorm.
Many people thought the bang was the start of an earthquake, or fireworks. The noise was heard across Groningen, and it turns out that there must have been a major lightning strike at Leens in the municipality of Het Hogeland.
Thunderstorms in the winter are dangerous as the clouds are lower; the chance of a lightning impact is much greater. Often there are fewer discharges of lightning in the winter, meaning that when they do happen they are often stronger.
According to the Meteologix website, there was a discharge of 186 kiloamps on Sunday evening at Leenstertillen, which is much heavier than normal lightning, where the number of amps is between 60 and 100.