If one averages the depth of ocean -through water to the bottoms- with the average height of dry land, the possibility of water covering the globe to a depth high enough to top Mt Ararat by fifty cubits is quite possible. All God would have to do is bring the bottoms of the oceans up to our current sea level, and the oceans would cover the Earth.
But our seal of assurance against that is the rainbow, whose absence would indicate there is no precipitation going on somewhere, even were it a snow-dog . . .
That is probably true bro. Tell that to a certain Freeper. Tell it to he who must be unnamed.
:-)