Cumulonimbus mammatus photo taken during sunset at the end of a severe thunderstorm. This photo links with the next Cb photo taken earlier on the day as a severe thunderstorm buffeted the Maltese Islands and which had developed very quickly over the Maltese Islands. The primary cause was an overhead cold pool at 500mb underneath a very moist easterly winds at the surface rendering a very unstable atmosphere over the Maltese Islands. Combined with a squall line (shown by the black line on the surface pressure chart) this very quickly led to the formation of cumulonimbus. The mammatus clouds are the result of descending air-masses after the quick ascent during the storm. Another photo of the mammatus cloud can be seen in the first thumbnail. The second thumbnail shows a very beautiful sunset photo on a stormy day as the setting sun reflects on the edges of cumulonimbus clouds. The third thumbnail shows this day`s sunset from a wider view along with the visible satellite image.