On what date did Genesis say the Flood waters begin?

Genesis says the Flood waters began on the 17th day of the second month.

Genesis 7:11 gives a highly specific date: in Noah’s 600th year, on the 17th day of the second month, the fountains of the deep burst open and the windows of heaven opened. The date is part of the narrative’s internal chronology rather than a date tied to a universally accepted historical calendar.

Genesis also records other dated milestones, including the Ark resting on the mountains of Ararat on the 17th day of the seventh month. These repeated day-and-month references create a structured timeline for the Flood account.

Readers sometimes confuse the beginning date with the later landing date or with the date Noah left the Ark. Those are separate events in Genesis 7–8, and the month references are not automatically equivalent to modern calendar months.