Formation of cumulus radiatus clouds behind approaching cumulonimbus cloud taken just after dawn. The first thumbnail is a closer look into this cloud showing that it was rather fragmented or could perhaps have been part of the cumulonimbus cloud. My thaught is that the circular movement of the cloud is due to the passage of the centre of a rather weak normal low pressure system that passed over our Islands with a clear eye as indicated in the visible satellite image on the sixth thumbnail. It was noticed that during the “eye” when this photo was taken, the wind was mostly calm but after the rain moved on, the wind suddenly increased to Force 5 from a NNE direction. It is also interesting to note that the same low pressure system became a Mediterranean cyclone Numa as it had stalled over the Ionian Sea acquiring ‘tropical’ characteristics. The weather charts illustrate this explanation. These cumulonimbus clouds were later followed by very thick cirrus spissatus clouds as per second thumbnail photo which still obscured the sun completely. The weather sounding was a moist profile in all atmospheric levels. Due to low light conditions, inferior photo quality is regretted.