This is a really strange sky phenomenon. Do you know what kind of massive cloud this could be? A giant cumulonimbus?
On October 6, 2014, giant storm clouds engulfed the city of Zacatlán in Mexico.
Learn how to recognize dangerous storm clouds here! And enjoy the pictures by Enrique Aquirre below:
I am always pretty much amazed about the different forms clouds take. This one over Zacatlán was pretty creepy!