In the Genesis story of Noah’s Ark, how many days and nights of rain are described?

In the Genesis story of Noah’s Ark, rain is described as falling for forty days and forty nights.

Genesis 7:12 uses this phrase when recounting the flood. The number forty is also prominent elsewhere in biblical narratives, where it often marks a lengthy or significant period. In the ark story, it describes the duration of the rainfall rather than the total time that the floodwaters remained on the earth.

That distinction matters because the flood narrative continues well beyond the forty days of rain. Genesis says the waters prevailed for a much longer period, and the account dates the recession of the waters and Noah’s eventual departure from the ark separately.

A frequent simplification treats forty days as the entire flood duration. In the biblical chronology, however, the rain, the period of high water, and the waiting before leaving the ark are different stages.