Formation of individual bundles of cumulus-like clouds, altocumulus at an altitude of around 4.5km due to mid-level instability caused by the general strong heating of the atmosphere in heatwave conditions over Southern Europe. Wind at that altitude was Force 4 from a NNE direction just behind the main North African ridge. Kindly notice the crepuscular rays or light beams which are diverging from the sun through such clouds revealing other thin altocumulus clouds in the foreground. Closeup of these light beams were photographed and revelaed in the first thumbnail. This photo was taken at sunset but light beams emerging from the sun when behind clouds could appear at any time of the day mostly from cumulus and isolated cumulonimbus clouds and altocumulus in the presence of dust or other thin clouds. A heat low pressure was present over the Central Mediterranean.