All the wellsprings of the great deep burst
and the casements of the heavens were opened.
…
And the Flood was forty days over the earth, and the waters multiplied and bore the ark upward and it rose above the earth. And the waters surged and multiplied mightily over the earth, and the ark went on the surface of the water. And the waters surged most mightily over the earth, and all the high mountains under the heavens were covered. Fifteen cubits above them the waters surged as the mountains were covered. And all flesh that stirs on the earth perished, the fowl and the cattle and the beasts and all swarming things that swarm upon the earth, and all humankind. All that had the quickening breath of life in its nostrils, of all that was on dry land, died. And He wiped out all existing things from the face of the earth, from humans to cattle to crawling things to the fowl of the heavens, they were wiped out from the earth. And Noah alone remained, and those with him in the ark. And the waters surged over the earth one hundred and fifty days.-- Genesis 7: 11, 17-24
Told you it was going to rain.
Robert Alter points out that we can see in this chapter how the Bible tightly maintains its circular rhythms and logic:
The surge of waters from the great deep below and from the heavens above is, of course, a striking reversal of the second day of creation, when a vault was erected to divide the waters above from the waters below. The biblical imagination, having conceived creation as an orderly series of divisions imposed on primordial chaos, frequently conjures with the possibility of a reversal of this process: biblical cosmogony and apocalypse are reverse sides of the same coin. The Flood story as a whole abounds in verbal echoes of the Creation story (the crawling things, the cattle and beasts of each kind, and so forth) as what was made on the six days is wiped out in these forty.
The artistry of this circularity has to be appreciated all the more when you understand that the Bible is a mishmash of many storytellers and editors, not only in terms of the books collected but also with respect to the material within the books. It is quite a patchwork, and while the roughness of such a process can be seen, the reader is still left with a striking design.