Formation of mammatus cloud structure. These clouds were caused by a shortwave at 500mb (see chart) creating a weak line of instability which also affected the Maltese Islands. However, the area was strongly capped (kindly refer to the weather sounding second attachment) hence only mid-level thunderstorms with some rain had occurred on the day. Of note is the surface wind around the Maltese islands blowing parallel from each other between the Western and Eastern side.