The rains began to fall on the 17th of Cheshvan of the year 1656 from creation (2105), flooding the earth and rising above the highest mountains. Only Noah and his family survived, in the ark built to that end by Divine command, and a pair of each animal species, who entered with him into the ark.
The following is a chronology of the Flood, as indicated by the dates and time periods given in the Torah's account and calculated by Rashi:
Cheshvan 17: Noah enters ark; rains begin.
Kislev 27: Forty days of rain end; begin 150 days of water's swelling and churning, during which the water reaches a height of 15 cubits above the mountain peaks.
Sivan 1: Water calms and begins to subside at the rate of one cubit every four days.
Sivan 17: The bottom of the ark, submerged 11 cubits beneath the surface, touches down on the top of Mount Ararat.
Av 1: The mountain peaks break the water's surface.
Elul 10:Forty days after the mountain peaks becom visible, Noah opens the ark's window and dispatches a raven.
Elul 17: Noah sends the dove for the first time.
Elul 23: The dove is sent a second time, and returns with an olive leaf in its beak.
Tishrei 1: Dove's third mission. Water completely drained.
Cheshvan 27: Ground fully dried. Noah exits ark.
(This chronology follows the opinion of the Talmudic sage Rabbi Eliezer; according to Rabbi Joshua's interpretation, the Flood began on Iyar 17, and all above dates should be moved ahead six months.)
Total time that Noah spent in the ark: 365 days (one solar year; one year and 11 days on the lunar calendar).
Link: See the Torah's account of the Great Flood, Rashi's commentary, and insights and interpretations from sages, scholars and mystics through the ages on the Noach Parshah Page
There are those who say that before we do any mitzvah, we must first understand why it needs to be done. Why else were we given a mind?
There are others who say we must just obey with simple faith. How else can we bond with One who is entirely beyond our understanding?
Abraham did both. He began with absolute faith, even when it was impossible to make sense of what he had been told to do. Yet he would not leave until his questions were answered and he had been given a way to understand.
“Don’t do a thing to the young man, for now I know that you are a G‑d fearing person.” (Genesis 22:12)
Abraham said to G‑d, “Let me present my case. First You told me that my descendants will be from Isaac. Then You told me to take him for an offering. Now You say I mustn’t do a thing to him…” (Rashi, citing Midrash)
That makes sense. Matters that are beyond our understanding can never be fit neatly into human reason. But neither can they be left in conflict.
Because if what you believe is true, it must be true everywhere. Even within your own limited human mind.