Gospel According to Saint Matthew, Chapter 24: 36 But of that day and hour no one knoweth, not the angels of heaven, but the Father alone.
Gospel According to Saint Mark, Chapter 13:32 But of that day or hour no man knoweth, neither the angels in heaven, nor the Son, but the Father.
The Greek in St. Mark is explicit - it says Christ as the Immortal Son knows with the Father both the day and the hour. What they know, their Holy Spirit Who is the third person of the Blessed Trinity the Holy Spirit the Paraclete, knows. The Holy Triune Omnipotent Omniscient All Holy Lord God, the Father and the Son and the Holy Spirit, Holy Holy Holy Lord God Pantocrator, Infinite and All Powerful Creator and Ruler over all that has been created, unrestrained and uncontained by their creation and ubiquitously present throughout all of creation knows all that has ever been and is and will ever be. This knowledge they have perfectly possessed from before all time and creation and have always perfectly possessed and will always perfectly possess.
They are not telling us the day and the hour and have not even told the elect angels nor any of the saints, including the blessed virgin Mary.
It will come on a sudden and there will be no escaping it.
The last book of the bible, the Apocalypse, tells us all the signs that lead up to it. Also included is the entire history of God's creation in types and prophecy.
See: The Apocalypse, the Book of the Revelation