In the Genesis flood story, how long did rain fall on Noah’s Ark?

In the Genesis flood story, rain fell on Noah’s Ark for 40 days and 40 nights. Genesis 7:12 states that the rain fell upon the earth for this period after Noah and the animals entered the Ark.

The 40-day rainfall is not the same as the entire duration of the flood narrative. Genesis also says that the waters prevailed on the earth for 150 days, and the story continues through the later recession of the waters and Noah’s eventual departure.

The number 40 has wider biblical importance. It appears in narratives involving extended testing, waiting or transition, including Israel’s wilderness journey and Jesus’ fast in the New Testament. In the Ark story, however, the specific statement concerns the length of the rain.

A frequent error is to answer 150 days for this question. That figure refers to the period during which the floodwaters prevailed in Genesis, whereas the stated rainfall lasts 40 days and 40 nights.