Formation of thick cirrus clouds due to an upper-level trough over the area. Thunderstorm clouds were in the vicinity around the Maltese Islands earlier on hence it is not clear whether they are blown-off ice crystals from previous cumulonimbus clouds or compaction of cirrus clouds. The first thumbnail is a widespread view of the cloud cover whilst the second thumbnail indicates the jet stream which had calmed down to 48kmh around the Maltese Islands as the centre of the upper-level trough moved closer to the Maltese Islands.