I read that the rounded area is 3600 miles across, which makes it half the earth's size. But the tail feature is tens of thousands of miles in length. As i said in the blog posting on the site, any lightning in this storm could easily incinerate a city! Imagine flying alongside this monster, just under the anvil portion-a giant dark mountain range of roiling clouds, glowing from within with continuous, massive lightning strikes. It would be the most terrifying, awe-inspiring thing ANY of us would ever witness.