Genesis says the Flood waters prevailed on the earth for 150 days.
Genesis 7:24 states that the waters prevailed for 150 days. This figure describes the period during which the waters remained dominant, not simply the duration of rainfall. Genesis separately says that rain fell for 40 days and 40 nights, which is why the two numbers should not be treated as interchangeable.
The narrative then turns to the waters’ decline and gives further dates for the Ark’s resting and Noah’s eventual departure. These details create a longer chronology than the rain alone.
Translations and interpretations can differ over how the flood chronology is harmonized, but the explicit figure in Genesis 7:24 is 150 days. It is one of the account’s clearest numerical statements.