The cloud meteorologically described here had transformed into altocumulus castellanus as the same cloud continued moving eastwards hence becoming especially evident when seen from the opposite side of the setting sun and illuminated by it. This is evident on the first two thumbnails. Such clouds usually develop into thunderstorms when seen in the morning as was the case here. They are a clear indication of mid-level instability. In this case, the cloud itself did not produce any thunderstorm as it was well to the east moving away from the area and weather conditions may have been becoming more stable. Of note are the non-descript altocumulus clouds on top of the rising cloud bubbles and some gaps in between the cloud elements in the cloud base. Therefore the proper classification of the photographed cloud is altocumulus castellanus radiatus perlucidus pileus althugh pileus is not associated with altocumulus hence only nondescrept cloud. This can be viewed much better on the first thumbnail and the second thumbnail shows that the cloud bubbles had overgrown the pileus layer or non descript altocumulus as officially described. From the weather sounding, a small layer of very humid airmass at the latitude of 3.7km was noticed and similar to pileus formation this humid air may have encouraged such non-descept altocumulus to form. Similar to cumuliform clouds, altocumulus castellanus may take on various forms and shapes. Finally, there seems to be the understanding that when cloud bubbles are developed from a common base it is described as altocumulus castellanus whilst patches of mid-level clouds having a crenelated appearance and strong sprouting may be more classified as cumulus congestus altocumulogenitus or cumulonimbus altocumulogenitus if having an anvil or the cloud is producing thunderstorms.