I'm not postive I have right name for those clouds. Dictionary says cumulous are flat and black on bottom. Those in Manila were not really flat on bottom, and they were pure white. On the troopship we used to sail under clouds that had rain coming down out of them and their bottoms were flat and black. We'd all get soaked, but fifteen minutes later we would be dry again. Actually we welcomed getting rain soaked, because we did not have fresh water showers. And in the tropics it was smart to bathe in rain with clothes on, the rain came down so hard. If it hit family jewels it was rather painful. And it did the laundry.