For how many days did the floodwaters prevail in the Genesis Ark story?

In the Genesis Ark story, the floodwaters prevailed for 150 days.

Genesis 7:24 says the waters prevailed upon the Earth for 150 days. Genesis 8 then describes God causing a wind to pass over the Earth, after which the waters gradually abated. This figure therefore describes the period of dominant floodwaters, not simply the period of rainfall.

The number is frequently confused with forty days and forty nights. Forty days refers to the rain in Genesis 7:12 and the initial rising of the waters in Genesis 7:17. The two durations are both important, but they are not interchangeable.

The account continues with the Ark resting on the mountains of Ararat, the appearance of mountain tops, and Noah's bird releases. These later events show that the narrative treats the flood as lasting considerably longer than the rainstorm itself.