In 2 Nephi 26, Nephi makes is now prophesy, which has come to pass. He said that there shall be many signs of Christ’s birth and death, among other things. There were signs! When he was born, there was a new star in the sky and three days with no night. When he died, there was a lot of destruction and no day for three days, or, rather, nights.
https://www.churchofjesuschrist.org/study/scriptures/bofm/2-ne/26?lang=eng&verse=#p