Cumulus cloud over the southwestern part of Malta due to a low pressure system coupled with instability. The same low pressure system produced Force 9 winds earlier that day (without thunderstorms) and the formation of Nimbostratus. From my experience in cloud observation, I am observing that you need more instability to produce cumulus clouds when surface winds are strong then with less strong surface winds. The first thumbnail pic shows another developing cumulus with what looks like cirrocumulus clouds. The second thumbnail shows rough seas in Ghar Lapsi due to a Westerly Force 8-9 wind on that previous night.