Formation of cumulonimbus with fibrous streak due to a developed intense area of low pressure over the Central Mediterranean caused by the entrance of a polar maritime airmass on the previous day. Click here for more details. The surface pressure chart is indicated in the 4th thumbnail showing that a cold front had passed over our Islands. The photographed clouds normally form following a cold front and the first thumbnail shows rough seas over Ghar Lapsi as the Maltese Islands were buffeted by strong Mistral wind with gusts up to 90kmh. The second thumbnail is the satellite image showing such cloud formation from space. March is normally a windy month over the Maltese Islands with such winds as in this case being caused by Wintry low pressure systems meeting an active jet stream overhead and strong March sunshine over the area creating contrast between hot African airmass and remaining cold air at higher latitudes.