Sudden formation of thin stratocumulus clouds as a low pressure system was approaching from Africa. A sudden increase of Sirocco (SE wind) was observed. In the photo, the mid-level clouds were still visible hence the term translucidus. These clouds most probably formed because of the warm airmass carried over from Africa by the SE wind collecting water vapour as it passed through the warm Mediterranean. This was then carried to cooler area over the Maltese Islands hence forming these clouds. As the air over land was probably slightly unstable, this led to the combined formation of cumulus and stratus hence forming transparent clouds but with grey shadings exactly as per the photographed cloud.